RKI Instruments GD-70D Operating Manual

Gas Detector Head

Part Number: 71-0446
Revision: P1
Released: 7/11/19

GD-70D Series

Operating Manual

Request for the Customers

• Read and understand this operating manual before using the detector.

• You must operate the detector in accordance with the operating manual.

• Regardless of warranty period, we shall not make any compensation for accidents and damage

caused by using this product.
The compensation shall be made only under the warranty policy of products or parts
replacement.

• Because this is a safety device, daily and biannual maintenance must be performed.

• If you find abnormalities in the detector, please contact our local representative immediately.

<Contents>

Request for the Customers ..................................................................................... 1

1 Outline of the Product .................................................................................................... 4

1-1 Preface ............................................................................................................. 4

1-2 Product Purp ose ............................................................................................... 4

1-3 Definition of DANGER, WARNING, CAUTION and NOTE .............................. 5

1-4 Method of confirmation for CE marking type .................................................... 5

2 Important Notices on Safety .......................................................................................... 6

2-1 Danger Statements ........................................................................................... 6

2-2 Warning Statements ......................................................................................... 6

2-3 Caution Statements .......................................................................................... 7

3 Product Components ..................................................................................................... 8

3-1 Main Unit and Standard Accessories................................................................ 8

3-2 Outline Drawing ................................................................................................ 9

3-3 Names and Functions for Each Part................................................................. 10

3-4 Operation Diagrams ......................................................................................... 14

4 Installation ...................................................................................................................... 16

4-1 Requirements ................................................................................................... 16

4-2 Precautions for Installation Sites ...................................................................... 16

4-3 Precautions for System Designing ................................................................... 18

4-4 Proper use of alarm contact ............................................................................. 19

4-5 Installing the Detector ....................................................................................... 20

4-6 Wiring the Detector ........................................................................................... 22

4-7 Making Tubing Connections ............................................................................. 34

4-8 Disposal ............................................................................................................ 35

5 Operation ....................................................................................................................... 36

5-1 Preparation for Start-up .................................................................................... 36

5-2 Starting Up the Detector ................................................................................... 36

5-3 Turning Off the Detector ................................................................................... 38

5-4 Basic Operation ................................................................................................ 38

5-5 Modes ............................................................................................................. 39

6 Detection Mode .............................................................................................................. 41

6-1 Gas Alarm Activation ........................................................................................ 41

6-2 Fault Alarm Activation ....................................................................................... 47

6-3 External Output Operation ................................................................................ 47

6-4 Other Functions ................................................................................................ 50

6-5 About LONWORKS (LN specification) ............................................................. 53

7 Alarm Test Mode ............................................................................................................ 57

7-1 Alarm Test Mode ............................................................................................... 57

8 User Mode ..................................................................................................................... 59

8-1 User Mode ........................................................................................................ 59

9 Maintenance Mode ........................................................................................................ 65

9-1 Environmental Setting 1 "2-9" ........................................................................... 70

9-2 Alarm Value Setting "2-9" - "SET 1" .................................................................. 71

9-3 Fault Alarm Test "2-9" - "SET 4" ....................................................................... 73

9-4 Environmental Setting 2 "2-10" ......................................................................... 74

9-5 Date/Time Setting "2-10" - "SET 1" .................................................................. 79

9-6 Energized/De-Energized Contact Setting "2-10" - "SET 6" .............................. 81

9-7 ETHERNET Setting "2-10" - "SET 18" ............................................................. 83

10 Maintenance .................................................................................................................. 86

10-1 Maintenance Intervals and Items ........................................................ 86

10-2 Calibration Overview ........................................................................... 86

10-3 Calibrating with the Target Gas ........................................................... 90

10-4 Calibrating with a Surrogate Gas (Sensors with Factors) ................... 93

10-5 Calibrating with a Gas Bag (Calibrating with HCl) ............................... 99

10-6 Calibrating with a Humidifier (MOS Sensors) ...................................... 103

10-7 Calibrating a Pyrolyzer Unit ................................................................. 107

10-8 Flow Rate Adjustments ........................................................................ 110

10-9 Replacing Parts ................................................................................... 112

- 2 - GD-70D

10-10 Storing the GD-70D ............................................................................. 115

11 Troubleshooting ............................................................................................................. 116

12 Product Specifications ................................................................................................... 119

12-1 Common Specifications ....................................................................... 119

12-2 Specifications for Each Model ............................................................. 119

12-3 Specifications for Each Sensor Type ................................................... 120

12-4 Full Scale and Alarm Points ................................................................. 123

13 Calibration Parts List...................................................................................................... 126

14 Replacement Parts List ................................................................................................. 129

Warranty Policy ....................................................................................................... 142

- 3 - GD-70D

GD-70D

4 - 20 mA specification

Analog transmission

GD-70D-NT

NT specification

2-wire type DC power-line communication

GD-70D-EA

EA specification

Ethernet and analog transmission (4 - 20 mA)

GD-70D-LN

LN specification

LONWORKS

1

Outline of the Product

1-1 Preface

Thank you for choosing our GD-70D Series gas detector head. Please verify that the model number of the
product you purchased is included in the specifications on this manual.

This manual explains how to use the detector and its specifications. It contains information required for
using the detector properly. All users must read and understand the operating manual before using the
detector.

1-2 Product Purpose

• This is a fixed type gas detector head which detects gas leaks in semiconductor factories, etc.

• The gas detector is a safety device, not an analyzer or densitometer which performs quantitative/qualitative

analysis/measurement for gases. You must understand the features of the detector before using it, so that
you can use it properly.

• The detector detects abnormalities in the air caused by the presence of gas (or oxygen deficiency) with the
built-in gas sensor unit. The concentrations of detected gases are shown on the LCD .

• The built-in pump in the detector draws gas to perfo rm gas detect ion.

• The detector has two-step gas alarm conta ct an d fau lt ala r m co nta ct.

• The detector outputs the gas concentration in 4 - 20 mA or digital data.

• The communication method for each specification is as follows.

GD-70D - 4 -

CE Marking

1-3 Definition of DANGER, WARNING, CAUTION and NOTE

This message indicat es that im proper hand ling may ca use serious d amage

DANGER

WARNING

CAUTION

on life, health or assets.

This message indicat es that im proper hand ling ma y cause serious d amage
on health or assets.

This message indicates that improper handling may cause minor damage on
health or assets.

NOTE

This message indicates advice on handling.

1-4 Method of confirmation for CE marking type

The CE marking is labeled on the detector in case of comply with CE marking. Please confirm the
instrument specification before using. Please refer to the Declaration of Conformity that is at the end of this
manual if you have CE marking type.
You can confirm instrument specification to see the CE marking as follows.

CE marking label (Back of front cover)

- 5 - GD-70D

Power Supply

2

Important Notices on S afety

2-1 Danger Statements

DANGER

This is not an explosion-proof device. You must not use it to detect gases exceeding the lower limit of explosion.

2-2 Warning Statements

WARNING

Before turning on the detector, always check whether the voltage is properly applied. Do not use an unstable
power supply because it may cause malfunction s.

Need of grounding circuit

Do not cut the grounding circuit or disconnect the wire from the grounding terminal.

Defects in protective functions

Before starting the detector, check the protective functions for defects. When defects are found in the protective
functions, such as protective grounding, do not start the detector.

External connection

Before connecting the detector to external equipment or an external control circuit, securely connect it to a
protective grounding circuit.

Tubing

The detector is designed to draw gases around it under normal atmospheric pressure. If excessive pressure is
applied to the sampling inlet and outlet (GAS IN, GAS OUT) of the detector, detected gases may leak from the
flow system and pose dangers. Be sure that excessive pressure is not applied to the detector when it is used.
Detected gases must be exhausted from the outlet (GAS OUT) on the bottom of the detector to a safe place
using an exhaust tube.

Handling the sensor unit

Do not disassemble the electrochemical type sensor unit (ESU) or galvanic cell type sensor unit (OSU) because
they contain electrolyte. Electrolyte may cause severe skin burns if it contacts skin and may cause blindness if it
contacts eyes. It may discolor or damage clothing. If contact occurs, ri nse the area immediately with a large
quantity of water.

Zero adjustment (AIR Adjustment) in the atmosphere

When zero adjustment (AIR Adjustment for oxygen deficiency alarm) is performed in the atmosphere, check the
atmosphere for freshness before beginning the adjustment. If other gases exist, the adjustment cannot be
performed properly and the detector will not properly detect gas.

Operation in a gas

Do not operate the detector in a place where flammable/explosive gases or vapors are present. Operating the
detector in such an environment will lead to extreme dangers.

Response to a gas alarm

Issuance of a gas alarm indicates that there are extreme dangers. Take proper actions based on your judgment.

GD-70D - 6 -

Definition of Terms

Do not use a transceiver (walkie-talkie) near the detector.

2-3 Caution Statements

CAUTION

Radio waves from a transceiver near the detector or its cables may disrupt detector operation. When using a
transceiver, it must be used in a place where it disturbs nothing.

Do not turn the detector on less than 5 seconds after it was turned off.

Restarting the detector less than five second s after turning it off may cause errors.

Verify that the reading on the flow rate indicator corresponds to the specified flow rate before using the
detector.

If it does not correspond to the specified flow rate, gas detection cannot be performed properly. Be sure the flow
rate is stable.

Attach the dust filter before using the detector.

Before using the detector, attach the specified filter to prevent disturbances by possible gas absorption or air
dust.
The dust filter used depends on the gas being detected. For more information on dust filters, please contact RKI.

Observe the operating restrictions to prevent condensation inside the tube.

Condensation formed inside the tube causes clogging or gas absor ptio n, w hich di sturb s acc urate gas detection.
Thus, condensation must be avoided. In addition to the installation environment, carefully monitor the
temperature/humidity of the sampled area to prevent condensation inside the tube. In particular, when detecting
a corrosive, water-soluble gas, such as a strong acid gas, the gas is undetectable and furthermore may corrode
internal parts. Please observe the operating restrictions.

Do not use the external output of the detector to control other devices.

This is not a control device. You are not allowed to use its external output to control other devices.

Do not disassemble/modify the detector, or change the settings unless necessary.

Disassembling/modifying the detector will invalidate the guarantee of the performance. Changing the settings
without understanding the specifications may cause alarm malfunctions. Please use the detector properly in
accordance with the operating manual.

Do not forget to perform regular maintenance.

Since this is a safety device, regular maintenance must be performed to ensure its safety. Continuing to use the
detector without performing maintenance will compromise the sensitivity of the sensor, thus resulting in
inaccurate gas detection.

- 7 - GD-70D

<Standard Accessories>

3

Product Components

3-1 Main Unit and Standard Accessories

<Main Unit>

• Operating manual

• Protective rubber cap (to be removed when using the

detector)

• Dedicated handling lever (for wiring)

• Dust filter

• Interference gas removal filter

(to be supplied with sensor units for certain gases)

GD-70D - 8 -

Pyro lyzer Uni t

(Unit: mm)

GAS IN

GAS OUT

Sensor unit display

Operating switch

Screw for grounding earth rod

External wire hole

Power switch

<Pyrolyzer Unit (PLU-70)(Option)>

* This is needed in “pyrolyzer + electrochemical type (ESU)” and “pyrolyzer + pyrolysis-particle type
(SSU)”.
For more information on the pyrolyzer unit (PLU-70), see the separate operating manual.

3-2 Outline Drawing

M5 mounting hole

Display

Protective cover for power switch

Connector for PLU

Connector for PoE

- 9 - GD-70D

Wall-mounted unit

Main unit

Pump unit

Sensor unit

MODE key

Lock lever

Sensor unit nameplate display window

Power lamp

First alarm lamp

Second alarm lamp

Fault lamp

⑪

⑫
⑬

⑭

bar indicator

⑮
⑯

indicator

⑰
⑱

indicator

⑲

⑳

connection indicator

CAUTION
the unit compromises its original performance or causes malfunctions.

3-3 Names and Functions for Each Part

The detector consists of the following units.

Each unit consists of precision parts. When a unit is detached, be careful not to drop it. Dropping

<Front Panel and Character LCD>



 TEST/SET key
 ▲key
 ▼key

Concentration

Alarm setpoint

indicator

Concentration

value display

Communication

indicator







Flow rate



Maintenance





Pyrolyzer unit

Unit display

Gas name display

Inhibit indicator

GD-70D - 10 -

MODE key

Used to enter User and Maintenance Mode.
It is also used to cancel or skip in a specific mode.

TEST/SET key

Used to enter the test mode.
It is used for confirmation in a specific mode.

▲ key

Used to change screens or change a value (UP).

▼ key

Used to change screens or change a value (DOWN).

Lock lever

Lever to lock the main unit. Push it to attach or detach the main unit.

Sensor unit nameplate
display window

Window to view information on the currently installed sensor.

Power lamp (POWER)

Power lamp. Turns green when the power is on.

First alarm lamp
(ALM1)

First alarm lamp. Turns red when the first alarm is reached.

Second alarm lamp
(ALM2)

Second alarm lamp. Turns red when the second alarm is reached.

Fault lamp (FAULT)

Fault lamp. Turns yellow when an abnormality is detected in the detector.

Gas name display

Displays the gas name in chemical formu la (e.g. Silane = SIH4).

Concentration value
display

Displays the gas concentration.

Unit display

Displays the unit according to the specification (ppm, ppb, vol%, %, %LEL).

Concentration bar
indicator

The detectable range (full scale = FS) is divided into 20 segments. The
increase in concentration is displayed in prop ortio n to the full scale.

Alarm setpoint
indicator

The alarm setpoints (AL1 and AL2) are indicated on the conc entr at ion bar.

Flow rate indicator

Displays the flow rate. When the line is in the middle of the indicator, t he
flow rate is normal (0.5 L/m in).

Communication
indicator

For GD-70D-NT, this indicator is displayed while transmitting data with the
upper unit (TX, RX).

Maintenance indicator

Displayed while in Maintenance Mode. When this indicator is displayed, the
alarm contact is disconnected and there are no alarms.

Inhibit indicator

Displayed when the inhibition (point skip) is set.

Pyrolyzer unit
connection indicator

Displayed when the dedicated pyrolyzer unit (PLU-70) is connected.

①

②

③
④
⑤
⑥

⑦
⑧

⑨

⑩
⑪
⑫

⑬
⑭

⑮

⑯

⑰

⑱

⑲
⑳

<Main Unit>

The main unit of the GD-70D houses the sensor unit, pump unit,
and circuitry for the detector. The main unit installs to the
mounting plate’s terminal plate.

<Pump Unit>

The pump unit gets installed in the main unit. It draws sample into the detector at 0.5 L/min.

- 11 - GD-70D

adjustment).

Mounting hole

10-point terminal plate: Connections for power supply,
signal cables and other external wires.

Locking lever: Locks the main unit to the mounting plate.

<Mounting Plate>

The mounting plate gets installed to the installation site. The main unit connects to the mounting plate
using the 10-point terminal plate.

<Sensor Unit>

A sensor unit installed in the detector is the same regardless of
the detection principle which means sensor units are
interchangeable. Each sensor unit has a different color that
corresponds to the detection principle as shown below. Handling
of the sensor unit depends on the detection principle.

CAUTION

• The sensor unit must be handled carefully to ensure quality. When the sensor unit is stored, a
dedicated warehouse and power equipment for the sensor unit are needed. In principal, the sensor
unit must not be detached from the detector when it is handled or stored.

• Be sure that the sensor unit is installed properly.
If a sensor unit is of different specification or principle than the one shipped from the manufacturer, a
message will be display ed on the dete ctor LCD (C-02).
If this message is displayed, make sure you are using the correct sensor unit.

• After the sensor unit is replaced, always perform a gas calibration (zero adjustment and span

GD-70D - 12 -

Electrochemical

• Do not disassemble the sensor unit because it contains electrolyte. If contact

Pyrolysis-particle

• Although the sensor unit contains radioactive materials, it is certified as a

Semiconductor

• Before using the sensor unit, it needs to be warmed up for a specified time.

Unpowered time
Suggested warm-up time

SGU-8541 (H2)

SGU (Others)

10 minutes or less

10 minutes or more

2 hours or more

1 hour or less

30 minutes or more

2 hours or more

24 hours or less

1 hour or more

4 hours or more

72 hours or less

4 hours or more

24 hours or more

10 days or less

2 days or more

2 days or more

Less than 1 month

7 days or more

7 days or more

Less than 3 months

14 days or more

14 days or more

3 months or more

1 month or more

1 month or more

Dedicated case

Dedicated case

type (ESU)

type (SSU)

occurs, rinse the area immediately with a large quantity of water.

• The sensor unit identifies the storage direction. Put the sensor unit in the
dedicated case while handling it. Do not place it on its side or upside-down.

• When a new sensor unit is installed, it must be warmed up.
Although warm-up time is different depending on the type of the installed
sensor, it is recommended that warm-up should be performed for three hours or
more. Please contact RKI for more information.

• The sensor unit must be stored in a clean, cool and
dark place away from direct sunlight. Some types of
the sensor units cannot be stored together with other
units. Please contact RKI for more information.

specified designing certification device, which is regarded as a device
having no influences on health. Observe the "Safety Manual" which
stipulates conditions for the certification. To dispose of the sensor unit, you
must return it to us. You do not need to take any additional actions.

• The sensor unit contains a small amount of radioactive materials. Do not
disassemble it, or dispose of it like other wastes.

• The sensor unit must be put into the dedicated case specified by us, and
stored away from direct sunlight in a clean place
where the temperature and humidity are maintained
at a normal level and where appropriate measures
are taken to prevent the sensor from being taken out
easily.

• When the sensor unit is transported out of your
factory, please use a transportation company which
can handle specified designing certification devices
(L-type packages).

• For more information, see the "Safety Manual".

type (SGU)

The sensor unit is warmed up sufficiently in our factory before it is delivered to
you. Therefore, after you receive the sensor unit, please use it as soon as
possible so that unpowered time is minimized.

• The warm-up time before using the sensor unit is related to how long the
sensor unit was unpowered .

• To store the sensor unit in an unpowered state, it must be stored under
normal temperature/humidity in a clean place away from direct sunlight.

- 13 - GD-70D

Galvanic cell type

• Do not disassemble the sensor unit because it contains electrolyte. If contact

Sensor unit

Flow

Pump

POWER INPUT (24

VDC)

Power supply part

Gas alarm contact

Alarm contact controller

Transmitter

EA specification)

Amplifier

Controller

Display

Operating unit

4 - 20 mA specification:

(OSU)

occurs, rinse the area immediately with a large quantity of water.

• The sensor unit must be stored under normal tem per atur e/humidity in a clean
place away from direct sunlight.

3-4 Operation Diagrams

<Electric Diagram>

(ALM1, ALM2)
Fault alarm contact
(FAULT)
* Standard setting of

GD-70D - 14 -

contact activation

De-energized

(De-energized at a
normal state)

ON-ALARM

(Closed contact at
an alarm state)

(4 - 20 mA/NT/

4 - 20 mA DC transmission
NT specification: Digital
data transmission
EA specification: Ether net
and 4-20 mA DC
transmission
LN specification: confirm to
LONWORKS

Controller

(CPU)

(CPU)

(POWER) (ALM1) (ALM2)

(FAULT)

LCD

(MODE) (▲) (▼) (TEST/SET)

Pump
control
circuit

sensor

<Tubing Diagram>

- 15 - GD-70D

working areas, carefully consider how many units to install and whe re to in stall t he m.

sensor unit.

4

Installation

4-1 Requirements

All users must follow the operating precautions. Ignoring the precautions may damage the detector,
resulting in inaccurate gas detection.

CAUTION

• After you receive the detector, start using the detector within the specified operation start limit of the

4-2 Precautions for installation sites

CAUTION

• This is a precision instrument. Because the detector may not provide the specified performance in
some places (environments), check the environment in the installation site, and then take
appropriate actions if necessary.

• Because the detector plays an important role for safety and disaster prevention, you must install as
many units o f the det e ctor a s nee ded in a pp ropri at e p oin ts.

• Because gases may leak or collect in different areas depending on the types of gases and the

Do not install the detector in a place with
vibrations or shocks.

The detector contains sensitive electronic parts. The detector
must be installed in a stable place without vibrations or shocks
and where it will not fall.

Do not install the detector in a place exposed to
water, oil or chemicals.

Avoid installation locations where the detector is exposed to
water, oil or chemicals.

Do not install the detector in a place where the
temperature drops below 0ºC or rises over 40ºC.

The operating temperatures of the detector are 0 - 40ºC. The
detector must be installed in a stable place where the operating
temperatures are maintained and do not change suddenly.

GD-70D - 16 -

Do not install the detector in a place exposed to direct
sunlight or sudden changes in the temperature.

Avoid installation locations where the detector is exposed to
direct sunlight or radiant heat (infrared rays emitted from a high­temperature object), and where the temperature changes
suddenly. Condensation may form inside the detector, or the
detector cannot adjust to sudden changes in the temperature.

Keep the detector (and its cables) away from
noise source devices.

Avoid installation locations where high-frequency/high-voltage
exist.

Do not install the detector in a place where maintenance of the detector cannot be
performed or where handling the detector involves dangers.

Regular maintenance of the detector must be performed.
Do not install the detector in a place where the equipment must be stopped when maintenance is
performed, where parts of the equipment must be removed to perform maintenance, or where the detector
cannot be removed because tubes or racks prevent access to it. Do not install the detector in a place
where maintenance involves dangers, for example, near a high-voltage cable.

Do not install the detector in equipment which is not properly grounded.

Before installing the detector in equipment, the equipment must be grounded properly.

Do not install the detector in a place where other gases exist around it.

The detector must not be installed in a place where other gases exist around it.

- 17 - GD-70D

Power supply voltage

or PoE connection (GD-70D-

EA)

Allowed time of

Up to 10 milliseconds (To

detector.)

Example of actions

Others

Do not use it with a power

frequency noise.

Example of actions

Protection against

Take appropriate measures in accordance with the importance of the facilities

Grounding

In addition to lightning, there are more sources of surge noise. To protect
devices from these noise sources, the devices must be grounded.

• An unstable power supply and noise may cause malfunctions or false alarms.

4-3 Precautions for System Designing

CAUTION

Using a stable power supply

The external output and alarm contact of the detector may be activated when the power is turned on, when
momentary blackout occurs, or when the system is being stabilized. In such cases, use a safety power
supply, or take appropriate actions on the receiving side.
The detector must be provided with the following power supply.

24 VDC ±10% (the terminal voltage of the detector)

momentary blackout

recover from a momentary
blackout longer than 10
milliseconds, restart the

supply that has a large
power load or high-

To ensure continuous operation and activation, install
a protective power supply outside the detector.

Use a line filter to avoid the noise source if
necessary.

Heat radiation designing

When it is installed in the closed instrumentation board, attach ventilation fans above and below the board.

Protecting against lightning

If cables are installed outside the factory/plant, or if internal cables are installed in the same duct as the
cables coming from outside the factory/plant, lightning will cause problems. Because lightning acts as a
large emission source while cables act as a receiving antenna, devices connected to the cables may be
damaged.
Lightning cannot be prevented. Cables installed in a metal conduit or under the ground cannot be
completely protected from a power surge caused by lightning. Although complete elimination of disasters
caused by lightning is impossible, the following protective measures can be taken.

lightning

and the environment.

• Connect the transmissi on sign al rout e by using optical fiber.

• Provide protection by a lightning arrester (cable safety retainer).

(Although indu ctiv e l igh tni ng su r ge can be t ran smi tted th ro ugh t he c abl e, it
is prevented by i n stalli n g a l ig htn ing a rre ste r be fo re t he fiel d dev i ces a nd
central processing equipment. For information on how to use a lightning
arrester, please contact the manufacturer.)

* The lightning arrester has a circuit to remove a surge voltage which damages field devices, so that

signals may be attenuated. Before installing a lightning arrester, verify that it works properly.

GD-70D - 18 -

GD-70D

SK1

SK2

Alarm

Contact

Power

Power

External relay
(low voltage relay)

* SK1, SK2: Surge absorbing parts

receiving side of the b cont act.

as a CR circuit.

4-4 Proper use of alarm contact

The alarm contact of the detector is used to transmit signals to activate an external buzzer, alarm lamp or
rotating lamp. Do not use the detector for controlling purpose (e.g., controlling the shutdown valve).

CAUTION

• The b contact (break contact) under de-energized state may be open ed momen ta rily by a physical
shock, such as external force.

• When the b contact is selected for the alarm contact, take appropriate actions to prepare for a
momentary activation by adding signal delay functionality (approximately one second) to the

The specifications for the alarm contact of the detector are based on the resistive load conditions. If
inductive load is used at the alarm contact, the following errors will occur easily because counter
electromotive force is generated at the contact.

• Deposition, defective insulation or defective contact at the relay contact

• Damage of any el e ctri c pa r ts due t o hi gh-voltage generated inside the detector

• Abnormal operations by an out-of-control CPU

CAUTION

• In principal, do not activate inductive load at the alarm contact of the detector. (In particular, never
use the inductive load to activate a fluorescent lamp or motor.)

• If inductive load is activated, relay it with an e xternal relay (c ontact amplifi cation). However, because
the coil of a n e xte rnal relay al so inv olv e s in du ctiv e l oad , sele ct a relay a t a low e r v ol tag e (1 00 VAC o r
below), and then p r otec t the c o ntac t of t he de te cto r wi th an ap p rop riat e sur ge ab sorbi ng pa r t, su ch

If load is to be activated, appropriate measures must be taken to stabilize the operation of the detector and
protect the alarm contact referring to the following information.

• Relay it with a n e x tern al rel ay at 100 VAC or lower (contact amplification). At the same time, the surge
absorbing part, SK1, suitable for the specifications must be attached to the external relay.

• In addition, the surge absorbin g part, SK2, must be attach ed to the loa ded side of the e xternal relay if
necessary.

• It may be recommended that the surge absorbing part be attached to the contact for certain load
conditions. It must be a ttac he d to an ap pr op riate po si ti on by che ckin g how t he loa d is activated.

Coil

Load

supply

- 19 - GD-70D

supply

be damaged. Do not forget to remove the caps.

Leave space for the crosshatched area when installing the detector.

resonance between them. In this case, take preventive actions like reinforcing the rack or wall.

Maintenance space

Maintenance space

Maintenance space

Maintenance space

Maintenance space

Maintenance space

When installing using 2 screws

When installing using 3 screws

(Unit: mm)

(300)

(90)

(300)

4-5 Installing the Detector

NOTE

To use the pyrolyzer unit (PLU-70), also refer to the individual operating manual.

CAUTION

• Before installing the detector, remove the protective rubber caps from the GAS IN and GAS OUT
fittings. If the detector is turned on while the rubber caps are still in place, the pump and sensor may

<Detector Dimensions and Maintenance Space>

CAUTION

• Multiple detectors installed in the same location must be installed at least 5 mm apart. It is
recommended that they be 10mm apart.

• When you install more than one detector in the same location, install them in a rack or on a wall that
is not affected by vibrations.
When the detectors are installed side-by-side, if the rack or wall in which the detectors are installed
does not have enough streng th, vibrations from the pumps inside the detectors can cause

The crosshatched space represents necessary maintenance space.

GD-70D - 20 -

Wall

Floor

Ceiling

Wall

CAUTION

• The detector must be installed in the correct orientation to ensure its performance. Install the
detector as shown on the follow ing ex ample. (* The dete ctor must al so remain in this orie ntati on
during transportation.)

<Correct Installation Orientation>

<Installing the Mounting Plate>

1. Make sure power to the detector is turned off.

2. While pushing the blue lever toward the mounting plate,
push the main unit up.

3. If you cannot move the main unit, insert a larger flathead
screwdriver into the mounting plate while pushing the lever
as shown to the right. Do not rotate or move the flathead
screwdriver. Simply insert it into the mounting plate.

4. Remove the silver mounting plate from the back of the GD-70D.

- 21 - GD-70D

For 3-wire type (common cable for
specification)

Shielded cable of CVVS, etc. (1.25 mm2) - 3-core

For 2-wire type (power and signal
specification)

Power: Cable of CVV, etc. (1.25 mm2) - 2-core

For 2-wire type DC power-line
specification)

Shielded twisted-pair cable of KPEV-S, etc. (1.25 mm2) ­For Ethernet (EA)

Power: Cable of CVV, etc. (1.25 mm2) - 2-core
Signal: Ethernet cable (category 5 or higher)

For PoE (EA)

Ethernet cable (category 5 or higher)

For LONWORKS output cable

・

1P

For contact

Cable of CVV, etc. (1.25mm2) - max. 6-core

• When stranded wires are used, prevent wires from contacting each other.

5. Attach the mounting plate to the installation surface using two or three M5 screws.

Recommended mounting screw (M5)
Length of 8 mm or more
Flat washer of φ10 mm or less (small round)

6. Leave the main unit detached from the mounting plate and continue to the wiring section.

4-6 Wiring the Detector

NOTE

To use the pyrolyzer unit (PLU-70), also refer to the separate operating manual.

CAUTION

• Be careful not to damage the in te rnal ele ct roni c cir cuit w h en w i ring. I n a ddi tio n, be care ful t o p rovi de
appropriate strain relie f w hen u si ng cabl e s for w i ring.

• The power cables and signal cables must not be installed together with the motor power cables, etc.
When these cables must be installed together for unavoidable reasons, put the power cables and
signal cables in a metal conduit. The conduit must be connected to a groundin g circuit .

<Recommended Cable>

power and signal) (4 - 20 mA/EA

cables separated) (4 - 20 mA/EA

Signal: Shielded cable of CVVS, etc. (1.25 mm2) - 2-core

communication system (NT

GD-70D - 22 -

1P

Shielded twisted pair cable of KPEV-S, etc. (1.25 mm2)

Dedicated

handling lever

Wiring hole

Driver slot

Conductive
part

Cage

Top handling slot

<Terminal Plate Specifications>

Specifications of terminal plate

• Rated voltage: 250 VDC

• Rated current: 16 A

Connection conditions

• Cable: 0.08 - 2.5mm2

• Bare wire length: 8 - 9 mm

• Connecting tool: Dedicated handling lever (accessory)

CAUTION

• The specified bare wire length must be observed when the wire insulation is peeled off.

• Be careful not to separate the wire strands.

Compatible bar terminal

For a bar terminal, the following items are available.

• Bar terminal (ferrule): Model 216 Series (manufactured by WAGO)

clamp/spring

• Crimping tool: Model VarioCrimp 4 (206-204) (manufactured by WAGO)

CAUTION

• A bar terminal of the specified model must be used. Using other bar terminals invalidates the
guarantee of the performance.

- 23 - GD-70D

1 2 3 4 5 6 7 8 9

10

+

－

+

－

24 VDC

4 - 20 mA

ALM1

contact

ALM2

contact

FAULT
contact

1 2 3 4 5 6 7 8 9

10

+

－

+

－

24 VDC

LONWORKS

output

ALM1

contact

ALM2

contact

FAULT
contact

<Wiring to the Terminal Plate>

● 4 - 20 mA/NT/EA Specification

●LN Specification

NOTE

For a 3-wire type 4 - 20 mA, terminal 2 is used as common for the power supply and the 4-20 mA output.
Therefore, wiring should be connected to terminals 1, 2, and 3 only. Terminal 4 can be left open.

For the NT specification, terminals 3 and 4 are not used.
For the EA specification with PoE connection, terminals 1 and 2 are disabled.

CAUTION

• The right tools must be used.

• Only one wire can be connec t ed to e a ch wi rin g hole .

• Do not connect a wire anywhere othe r than a wi ring hole.

1. Make sure power to the detector is turned off.

2. While pushing the blue lever toward the mounting plate,
push the main unit up.

3. If you cannot move the main unit, insert a larger flathead
screwdriver into the mounting plate while pushing the lever
as shown to the right. Do not rotate or move the flathead
screwdriver. Simply insert it into the mounting plate.

GD-70D - 24 -

Push the dedicated

Push the lever with your
in its inside.

While holding down the lever, insert the

lever is released, the wire is secured.

4. Use the handling lever included with the GD-70D or a
flathead screwdriver to make wiring connections.

5. Route the wires through the wiring opening in the bottom of
the mounting plate.

6. Insert the handling lever into the driver slot associated with
the terminal you are wiring.

7. Push the lever toward the terminal plate so the protr us ion on
the lever goes into the top handling slot and opens the
wiring hole. If you are not using the handling lever, push
down into the top handling slot with a flathead screwdriver.

8. Hold the lever down while you insert a wire into the wir i ng
hole.

9. Release the lever. Gently pull on the inserted wire to make
sure it is connected.

10. Repeat for all other wiring connections.

finger to lower the spring

wire into the (round) wiring hole until it
reaches the deepest point. Once the

handling lever to
open the terminals.
Insert 1 wire per
terminal.

- 25 - GD-70D

ALM2

FAULT

3

4

5

6 7

8

9

10

+

-

ALM1

4-20mA

Device

Power

Device

Power

Alarm

1

Device

Alarm

2

Device

Fault Alarm

Device

+

24VDC

Controller

orRecording

Device

1

+

- (DC Ground)

4

-

20mA

In (FB)

GD-70D Terminal

Plate

DC24V

2

-

Cable

Shield

Device

Power

Generic Controller Wiring

GD-70D - 26 -

FAULT

3

4 5 6

7

8 9

10

+

-

ALM1

4-20mA

ALM2

Device

Power

Device

Power

Alarm

1

Device

Alarm 2

Device

Fault Alarm

Device

Power Supply

1

+

- 24VDC

+24 VDC

Device

Power

+

-

PLC orDCS

Cable

Shield

CableShield

GD-70D

TerminalPlate

DC24V

2

-

PLC or DCS Wiring

- 27 - GD-70D

FAULTALM2

4-20mA

ALM1

-

+

10

9876543

Fault Alarm

Device

Alarm 2

Device

Alarm 1

Device

Device

Power

Device

Power

13
14

12

+

1

Device

Power

11

RM-5003

Cable

Shield

-

2

DC24V

GD-70D TerminalPlate

RM-5003 Wiring

GD-70D - 28 -

76543

FAULT

ALM2

4-20mA

ALM1

-

+24 VDC

Fault

Alarm

Device

Alarm 2

Device

Alarm 1

Device

Device

Power

Device

Power

RJ45

Connector

+

10

98

Switching

Hub

PC or

PLC

+

1

Power

Supply

Device

Power

-

24VDC

-

2

DC24V

GD-70D Terminal

Plate

Cable

Shield

Ethernet Wiring

- 29 - GD-70D

9

10

+

-

ALM1

4-20mA

ALM2 FAULT

3

4

5 6

7 81

+

Device

Power

Device

Power

Alarm 1

Device

Alarm 2

Device

Fault Alarm

Device

PC or

PLC

Switching Hub

(with PoE

Functionality)

RJ45

Connector

GD-70D TerminalPlate

DC24V

2

-

Device

Power

PoE Wiring

GD-70D - 30 -

FAULT

ALM2

ALM1

-

Device

Power

LON

WORKS

+

10

98

7

65

4

3

Power

Supply

+

24

VDC

Fault Alarm

Device

Alarm 2

Device

Alarm

1

Device

Device

Power

+

1

Device

Power

LON

- 24

VDC

-

2

DC24V

GD-70D

Terminal

Plate

Cable

Shield

CableShield

LON Wiring

- 31 - GD-70D

3 4 5 6 7 8 9 10

+

-

ALM1

4-20mA

ALM2

FAULT

Device

Power

Alarm 1

Device

Alarm 2

Device

Fault Alarm

Device

1

+

Device

Power

Blocking Filter

(B/F)

+

-

Power

Supply

(24 VDC)

DC

24V (-)

DC

24V(+)

Upper

Unit

(RM-70NT)

GD-70D-NT

Terminal

Plate

DC24V

2

-

Cable

Shield

+ -

Device

Power

Position the

RM-70NT Wiring (for GD-70D-NT)

<How to Clamp Cables>

1. Insert the supplied zip tie into the hole on the mounting plate
as shown in the figure to the right.

2. Position the zip tie so that its coarse side faces the wires.

3. Tighten the zip tie to secure the wires.

NOTE

When an optional cable gland is used, it must
be attached to the external wiring hole.

band so that
its coarse
side faces the
wire.

GD-70D - 32 -

Grounding screw (M4)

Bottom

When the main unit is fully

10mm

When reinstalling the main unit,

plate hook before pushing down.

The lock clicks.

<Grounding>

Use the grounding terminal to connect the detector to your
grounding circuit.

WARNING

• Before turning on the detector, do not forget to connect it
to a grounding circuit.

• For stable operation of the detector and safety, it must be
connected to a grounding circuit. Do not connect the
grounding wire to a gas pip e. The groundi ng must be

made as D type grounding (below 100 Ω of grounding

resistance).

<Attaching Main Unit to Mounting Plate>

1. Make sure power to the detector is turned off.

2. Position the main unit about 10 mm above the mounting
plate.

3. Lower the main unit toward the mounting plate. Be sure both
mounting plate hooks fit into the main unit grooves.

4. Press down on the main unit to secure it. The lock at the
bottom of the main unit clicks to fix it properly.

5. Make sure that the top center of the mounting plate is above
the main unit as viewed from front. If it is not, push the main
unit down farther.

align the arrow mark on the side
of the housing with the mounting

installed on the mounting plate,
the top of the mounting plate will
protrude above the main unit.

- 33 - GD-70D

4mm x 6 mm
Teflon Tubing

Nut

Tubing Insert

Ferrule

Dust Filter

Gas Inlet

To Sample Area

4-7 Making Tubing Connections

NOTE

To use the pyrolyzer unit (PLU-70), also refer to the individual operating manual.

1. The tube nut, ferrule, and tubing insert are shipped uninstalled and the open GAS IN and GAS OUT
fittings are plugged with protective rubber caps. Remove the rubber caps from the GAS IN and GAS
OUT fittings.

2. Install a short piece of 4 mm x 6 mm Teflon tubing to the GAS IN fitting as shown below. Be sure the
tubing insert, ferrule, and nut are installed properly.

3. Connect the dust filter to the tubing.

4. Install another piece of 4 mm x 6 mm Teflon tubing to the other end of the dust filter and route it to the
sample area.

5. Attach 4 mm x 6 mm Teflon tubing to the GAS OUT fitting and route it to a safe area. Be sure to use
the tubing insert, ferrule, and nut as shown above.

GD-70D - 34 -

leading to dangers. Be sure that excessive pressure is not applied to the detector during use.

Please contact RKI for help determining an inlet tubing length.

Manual". We wil l p rope rly di sp o se o f it . Ig no ring the "Sa fe ty Manual" will result in legal p enal tie s.

WARNING

• The detector is designed to draw gas under normal atmospheric pressure. If excessive pressure is
applied to the GAS IN or GAS OUT fitting, detected gases may be leaked from its inside, thus

CAUTION

• Keep the inle t li ne a s sho rt as po ssi ble to mini mize the abs or pti on o f ga s by th e sa mple t ubin g.

• When the humidity in the sampling point is high, condensation may be formed inside of the tube.

Make sure to avoid condensation when detecting water-soluble gases such as a strong acid gas,
because it may corrode internal parts. Also avoid loopi ng or kinking th e tubing .

•

4-8 Disposal

• A used sensor unit must be returned to RKI.

• If any liquid leaks from the electrochemical type sensor unit (ESU) or galvanic cell type sensor unit (OSU),

do not touch the li qui d. I f any l iqu id lea ks w hi le th e sen sor uni t i s in s tal led in t he de tecto r, turn off power to
the detector and contact RKI immediately.

• Because the pyrolysis-particle type sensor unit (SSU) contains a small amount of radioactive materials, it
must be transported appropriately (as a L-type package). When the sensor unit is returned to us, it must be
handled by a tran spo rtati on c o mpa ny whi ch can h andl e L -type packages.

• When the main unit is disposed of, it must be treated properly as an industrial waste in accordance with the
local regulation s.

WARNING

• Do not disassemble the electroche mical ty pe sensor uni t (ESU) or the gal vani c cell type sen sor unit
(OSU) because t hey con tain el ec t roly te.
Electrolyte may cause severe skin burns if it contacts skin and may cause blindness if it contacts
eyes. Electrolyte may damage or discolor clothing. If contact occurs, rinse the area immediately with
a large quanti ty o f wate r .

• The pyrolysis-particle type sensor unit (SSU) must be returned to us in accordance with its "Safety

- 35 - GD-70D

OFF

ON

Slide

Switch cover closed.

Switch cover open.

Power switch

5

Operation

5-1 Preparation for Start-up

Before connecting a power supply, read and understand the following precautions. Ignoring these
precautions may cause an electric shock or damage the detector.

• Connect the detecto r to a groundi ng cir cuit.

• Ensure the wiring is correctly connected to the external circuit.

• Ensure the main unit is properly installed on the mounting plate.

• Ensure the power supply voltage i s approp riate (s ee Specifi cation s).

• Alarm contacts may be activated during startup. Take steps to ensure this does not have any unwanted

effects.

• Verify that the GAS IN and GAS OUT lines are clear.

• Verify that the dust filter is installe d corre ctly.

5-2 Starting Up the Detector

1. The power switch is protected by a cover to prevent accidental
access. Rotate the switch cover to gain access to the power
switch. (Return the switch cove r to the original position once
you are done.)

2. Turn ON the power switch.

3. After the detector completes the start-up, it enters Detection
Mode.

(under cover)

GD-70D - 36 -

Power On

↓

PW

A1

A2

F

LCD

Initial Clear

● ○ ○

○

──────

↓

↓

Gas

● ○ ○

○

15.0ppm

↓

↓

Detection Mode

● ○ ○

○

0.0ppm

started.

PW:POWER

F:FAULT

●

<Warm-up Sequence>

The warm-up taking approximately 25 seconds to complete.

A1:ALM1
A2:ALM2

WARM UP

Specifications
Display

SIH4

SIH4

WARNING

• When Oxygen (OSU) is selected, fresh air (20.9 vol%) is
the output after the detector is started in the atmosphere.
For a specification where an alarm is triggered by the
AIR (normal oxygen concentration) output (e.g., 0 - 5
vol%), be careful of an alarm issue after the detector is

CAUTION

• Do not turn off the detector during the initial clear. The detector is reading the sensor memory during
the initial clear.

• If a new sensor unit is installed or the sensor unit is replaced after the detector is started, the sensor
unit must be w armed up fo r a spe ci fied pe rio d w hi ch i s de te r mined d epen din g on the type of the
sensor unit. Suggested warm-up time for SGU ty pe senso r un it s i s di splay ed in Mai nt ena n ce Mod e.
During the warm-up, the alarm activation and output signals are unstable. Prepare appropriately for
false alarms.

• Because the pyrolyzer unit (PLU-70) must be warmed up for one hour, please warm it up with the
detector.

• After the warm-up is completed, verify that the reading on the flow rate indicator corresponds to the
specified flow rate, and then perform a gas calibration.

:Lamp on

○:Lamp off

- 37 - GD-70D

"OFF" the detector.

<<Detection Mode>>

PW

A1

A2

F

LCD

● ○ ○

○

0.0ppm

<<User Mode>>

PW

A1

A2

F

LCD

● ○ ○

○

1- 1

MAINTENANCE

<<Maintenance Mode >>

PW

A1

A2

F

LCD

● ○ ○

○

2- 0

MAINTENANCE

<<Gas Alarm Test Mode>>

PW

A1

A2

F

LCD

● ○ ○

○

0.0ppm

MAINTENANCE

<<Fault Alarm Status>>

PW

A1

A2

F

LCD

● ○ ○

●

E-5

<<Gas Alarm Status>>

PW

A1

A2

F

LCD

● ● ○

○

6.0ppm

MODE

TEST

The detector is

MODE

PW:POWER

F:FAULT

●

5-3 Turning Off the Detector

To turn off the detector, open the switch cover on the bottom of the main unit, and turn "OFF" the power
switch. Then, turn off the power supply (24 VDC) to the detector.

WARNING

• When the detector is turned off, an alarm may be activated on the up pe r ( cent ral) system.
Before turning off the detector, the inhibit (point skip) on the upper (central) system must be
activated.
Decide whether the power can be turned off by checking the operation of the devices connected to
the external output or external contact output terminal of the detector.

• If the alarm contact is energized (option), they will activate when the detector is turned "OFF".

• If the detected gas is absorptive, the detector must be flushed thoroughly with fresh air before turning

5-4 Basic Operation

After the warmup procedure, the detector enters detection mode.

restarted after
recovering from
Fault.

SIH4

FLOW

TEST OFF

SIH4

(press and hold)

(press and hold)

A1:ALM1
A2:ALM2

GAS TEST

:Lamp on

○:Lamp off

(press and hold)

ZERO

GD-70D - 38 -

Mode

Item

LCD Display

Details

Detection
Mode

-

Gas concentration
Gas name

Normal state

Gas Alarm
Test Mode

User Mode

Zero Adjustment (Span

1-1 ZERO

oxygen)

Perform the zero adjustment (span adjustment for oxygen).

• Sensitivity c orrection ON/OFF

Flow Rate Indicator

1-3 FLOW

Show the current flow rate.

Address Display

1-4 ADDRESS

Show the address.

Detector Version Display

1-5 70D VER

Show the program version of the main unit.

Unit Version Display

1-6 UNIT VER

Show the program version of the sensor unit.

Net Version Display

1-7 NET VER

Show the program version of the communication function.

Access

this case, you must identify the causes and take appropriate actions.

Flow rate

Flow rate

Normal

flow rate

WARNING

• When the detector enters each mode from Detection Mode while an alarm is activated, the alarm
contact is released.

<Detection Mode>

Flow Rate Indicator

Because the suction flow rate of the detector is automatically adjusted by the flow rate control function, the
flow rate, in principal, does not need to be controlled. As shown on the figure below, when the flow rate
does not correspond to the specified flow rate for some reasons, it is adjusted automatically.

CAUTION

• If the automatic flow rate adjustment does not wo rk (due to clogg ed tube or lea k), you may get a
"FLOW" message (for an unstable flow rate) or an "E-05" message (for flow rate abnormal iti es). In

too low

too high

5-5 Modes

Details on each mode are provided as follows. (* Operations are slightly different depending on the
detector type or sensor unit.)

- Gas concentration Perform the alarm test.

(see pg. 59)

Adjustment for oxygen)

Setting Display 1-2 CONFIRM S how the setting of typical menus.

Maintenance Mode

(1-1 SPAN for

First alarm setpoint (AL1)

•

•

Second alarm setpo int (AL2)

•

Alarm delay time

•

Zero suppression value

•

Zero follower ON/OFF

1-8 M MODE Enter maintenance mode.

- 39 - GD-70D

Mode

Item

LCD Display

Details

Maintenance

Gas Introduction Display

2-0 GAS TEST

Perform the gas introduction test.

Zero Adjustment

2-1 ZERO

Perform the zero adjustment.

Span Adjustment

2-2 SPAN

Perform the span adjustment.

Last Calibrated Date

2-3 LAST CAL

Show the last calibrated date.

Voltage)

(2-4 E VOLT)

(Show the element voltage.)

Flow Rate Setting
(adjust ed to 0.5 L/m in)

2-5 DEF FLOW

Set the flow sensor wit h the flow ra te at 0.5 L/min.
Indicator

Detector Temperature

2-7 TEMP

Show the current temperature of the installation environme nt.

Completion Date/Time

(SGU).

Environmental Set ting 1

2-9 SETTING1

Operation settings

Fault test (F TEST)

• Pump drive level diagnosis ON/OFF setting (PUMP CK)

Pyrolyzer Data Display

2-11 PL DATA

If a pyrolyzer unit is being used, this menu displays data for it (see
the PLU-70 operator’s manual for more description)

Fault Investigation

2-12 FAULT

Not used

Factory Mode Switching

2-13 F MODE

Not used

Mode (see pg.

67)

Bias Voltage (Element

Pump Ratio/Flow Rate

Suggested Warm-up

Environmental Set ting 2 2-10 SETTING2 Function settings

2-4 BIAS

2-6 FLOW Show t h e output and flow rate of the current pump.

2-8 WARMTIME Show the suggested warm-up completion for semiconductor type

Show the bias voltage.

• INHIBIT setting (INHIBI T)

•

Alarm value setting (ALM P)

•

Alarm delay time setting (ALM DLY)

•

Regular replacement operation (pump stop) (MAINTE)

•

•

Address setting (ADDRESS)

•

Date/ Time s etting ( D AY TIME)

•

Zero suppression value setting (SUPPRESS)

•

Zero suppression system setting (SUP TYPE)

•

Alarm test time contact setting (TEST RLY)

•

Alarm test time external output setting (TEST4-20)

•

Energized/De-energized setting (RLY PTRN)

•

Alarm type setting (ALM TYP)

•

Alarm activa ti on setting ( A LM PTRN)

•

Alarm value limiter setting (AL LIMIT)

•

Fault activation setting (FLT PTRN)

•

Flow ra te auto-adjustment setting (AT FLOW)

•

Zero follower ON/OFF setting (ZERO F)

•

24 hours zero follower ON/OFF setting (ZERO 24F)

•

Sensitivity correctio n O N/OFF setting (S ASSIST)

•

External output in maintenance mode setting (MNT OUT)

•

External output adjustment (MA 4-20)

•

Backlight setting (BK LIGHT)

•

ETHERNET setting (ETHERNET)

GD-70D - 40 -

6

Detection Mode

6-1 Gas Alarm Activation

A gas alarm is activated when the concentration of detected gas reaches or exceeds the alarm setpoint.
This section describes alarms assuming an auto-reset operation.

NOTE

The alarm setpoint (first alarm and second alarm) is factory set.

The alarm delay time (standard: 2 seconds) is enabled in the detector to prevent a false activation. It can
be disabled, if desired.

<Display Operation During Alarm Condition>

Gas Concentration Display

The gas concentration is displayed on the LCD. If the concentration is above the detection range (over
scale), "∩∩∩∩" is displayed on the LCD instead of the gas concentration.

Alarm Indicator Lamp (ALM1: Red), (ALM2: Red)

When the first alarm setpoint has been reached, the ALM1 LED turns red.
When the second alarm setpoint has been reached, the ALM2 LED turns red.

GD-70D - 41 -

<Contact Activation>

The contact is activated when the gas concentration reaches or exceeds the alarm setpoint. The contact
activation is reset automatically when the gas concentration drops below the alarm setpoint.

<Contact Activation (Auto-reset)>

In case of Auto-reset setting, the contact is activated when the gas concentration reaches or exceeds the
alarm setpoint value. The contact activation is reset automatically when the gas concentration drops below
the alarm setpoint value.

NOTE

In DETECTION MODE, select and press one of the following key to reset : “MODE”, “▲”, “▼” or
“TEST/SET”.

"Alarm Pattern (H-HH)"

GD-70D - 42 -

"Alarm Pattern (L-H)"

"Alarm Pattern (L-LL)"
(* oxygen deficiency alarm)

- 43 - GD-70D

<Contact Activation (Self-latching)>

In case of Self-latching setting, the contact is activated when the gas concentration reaches or exceeds the
alarm setpoint value. The alarm indication lamp blinks during warning. It changes to a light after reset is
performed. It turns off when the gas concentration drops below the alarm set point value.

"Alarm Pattern (H-HH)"

GD-70D - 44 -

"Alarm Pattern (L-H)"

- 45 - GD-70D

"Alarm Pattern (L-LL)"

<Response to Gas Alarm>

When a gas alarm is triggered, take actions in accordance with your company’s safety practices for a gas
alarm. In general, take the following actions.

1. Check the reading of the detector.

NOTE

If a gas leak is momentary or if the alarm is triggered by noise, the reading may already have dropped by
the time you get to the instrument to check it.

2. Based on your company’s safety practices, no one can be allowed to a cces s t he monit ored z one to en su re
safety.

3. If the detector display is still indicating the presence of gas, close the area’s main gas valve, and then verify
that the detector’s gas concentration readin g dropp ed.

4. While wearing protective equipment in case gas is still present, use a portable gas detector to ensure the
area is free from gas.

5. If you can determine that the leak point is free from dangers, take actions to fix the gas leak.

GD-70D - 46 -

Specifications/Condition

4 - 20 mA (for GD-70D)

Power-line communication system

* E-5 FLOW (flow rate abnormalities)

6-2 Fault Alarm Activation

A fault alarm is triggered when the detector detects
abnormalities.

After a fault alarm is triggered, the FAULT lamp (yellow) lights up
and an error message is displayed on the LCD.

Determine the causes and take appropriate actions.
After the detector is successfully returned from the fault, it

restarts and goes through a normal warmup procedure.
If the detector has problems and is repeatedly malfunctioning,

please contact RKI immediately.

NOTE

For information on error messages and possible malfunctions, see Troubleshooting on page 116.

6-3 External Output Operation

● 4 - 20 mA/NT/EA Specification

Signal Transmission System Electric current transmission (non-isolated)

Transmission Path CVVS KPEV-S
Transmiss ion Distance Below 1 km

Connection Load Resistance Below 300 Ω -

Detection Mode (No Alarm) 4 - 20 mA (concentration output) Concentration data



Detection Mode (Gas Alarm) 4 - 20 mA (concentration output) Concentration data, Alarm bits



Initial Clear



Maintenance Mode



Alarm T est



Depending on the setting of 

2.5 mA setting: 2.5 mA
4 mA, HOLD, 4-20 mA setting: 4 mA*

2.5 mA setting : 2 .5 mA
4 mA setting: 4mA*
HOLD Setting: the previous value retained
4-20 mA setting: 4 - 20 mA (concentration output)

Output ON setting: 4 - 20 mA (concentration output)
Output OFF setting: In accordance with setting of



Fault Alarm 0.5 mA (Fixed) Fault bits



Inhibit



Power Off 0 mA Signal OFF



Depending on the setting of 

2.5 mA setting : 2 .5 mA
4 mA, HOLD, 4 - 20 mA setting: 4 mA*

* 17.4 mA for oxygen units

2-wire type DC power-line communication
system

Below 300 m (depending on the system
designing conditions)

Initia l bit

Concentration data, Adjustment bit

Concentration data, Adjustment bit, Test bit

Concentration data, Adjustment bit, Inhibit bit

(for GD-70D-NT)

- 47 - GD-70D

Specifications

LONWORKS (LN)

Signal
method

Transmission
path

Transmission
rate

Transmission
distance

Max 2700m
* When bus topology (Double ended termination ) is used.

Connection load
resistance

Maintenance output setting

Sensor unit

Details

2.5 mA

Use OSU (L-LL, L-H).

Output 2.5 mA during maintenance or inhibit.
alarm)

4 mA, HOLD, 4 - 20 mA

Specification change

When changing from a H-HH alarm pattern to

change message is confirmed.

Specification change

When changing from an L-LL or L-H alarm

“C-02” change message is confirmed.

2.5mA

4mA

20mA

22mA

Full scale

Gas concentration

External output

Zero
suppression

Detection mode

Maintenance mode

● LN Specification

transmission

Example of Gas Concentration and External Output
4 - 20 mA Specification
(Maintenance output: 2.5 mA setting)

CAUTION

<<4 - 20 mA Specification>>

• The 4 - 20 mA output is already adjusted. In case of over scale, an output will not exceed 22 mA.

• Output during inhibit or warmup is based on 4 - 20 mA output setting in Mai ntenan ce Mode.

Special Cases>

<

LONWORKS

KPEV-S
78kbps

―

The output may dro p a s low a s 2 .5 mA du rin g wa r mup for o xygen uni ts . Unde r stand how the
detector functions, and take actions to prepare for false alarms.

Possibility of false alarm in the upper unit (L

(To OSU - 0 - 25 v ol%)

(From OSU - 0 - 25
vol%)

an L-LL or L-H alarm pattern, 4 mA (equivalent
of concentration zero) is used until the “C-02”

pattern to a H-HH alarm pattern, 17.4 mA
(equivalent of approx. 84%FS) is used until the

GD-70D - 48 -

GD-70D-

Power-line
system

The detector is used in a local net work formed with a multi-displa y unit (RM­multi-display unit.

GD-70D-

Ethernet

The detector offers functions that work in liaison with external software using

value or perform calibration and test.

GD-70D-

LONWORKS

An internationally standardized network specification for device control. It is a

flexibility.

<Communication Specifications>

NT

communication

EA

LN

70NT) as the base unit. For more information, see the operating manual of the

a standard network protocol. For details, see the separate manual for
communication function.
Web function (HTTP), mail send function (SMTP), and time synchronization

function (SNTP)
Use a Web browser of an upper-unit PC to view and change setting values
and perform calibration and test on a graphical user interface.
SMTP, when receiving a gas alarm or fault alarm from an external mail
server, can send a notification mail to a registered address.
SNTP, receiving time information from a time server, can correct the clock at
regular intervals.
Modbus slave function (Modbus/TCP)
Works as a Modbus slave and feeds back a setting value in response to a
read request or changes a setting value in response to a write request.

PLC linkage function (FINS・MC)
Sends a setting value to PLC to provide information to be processed by PLC

in a ladder program. Reading from PLC is also available to change a setting

network specification that controls and manages not only gas detectors but
also air conditioning, lighting etc. equipment by the same communication
protocol called Lon-talk.
By constructing an open system, it becomes possible to connect the system
without being bound by one manufacturer, it is possible to facilitate
procurement of parts at the time of equipment failure, and to increase design

- 49 - GD-70D

<<Example: SiH4 0 - 15 ppm range>>

0.5ppm

SIH4

Suppression Disabled

↓

0.0ppm

SIH4

Suppression Enabled

6-4 Other Functions

<Suppression Function>

Some sensors are influenced by environmental changes (temperature, humidity, and other characteristics)
or interference gases which may cause the reading to vary in fresh air.

The suppression function is used to hide (suppress) the variation of the reading under the set suppression
value, so that the display indicates zero (or 20.9% for oxygen) until the reading exceeds the set
suppression value.

The factory setting for the suppression function is OFF for every gas type except for oxygen.

A variation around zero is displayed as the reading.

A variation under the set suppression value (ie. 6% of full scale or 0.9 ppm for

CAUTION

• If the zero reading is BELOW zero, the reading wil l not chang e until the reading reache s -10% of full
scale.

• A reading that is -10% of full scale is di splay ed as "-0.0".

SiH4) is shown as zero.

GD-70D - 50 -

sensor. To correct the sensitivity variation, you must regularly calibrate the sensor.

* The zero drift is periodically corrected to bring the

Zero Follower On

Zero Follower Off

* The zero drift of the sensor appears as the reading.

Reading

Zero point

0

Time

↓

Zero point

0
Reading

Time

Sensitivity Correction Off

* Sensor accuracy decreases.

Sensitivity Correction On

* The span is periodically lifted to

increase sensor accuracy.

↓

0

Time

Gas correction

Reading

Gas
0

Reading

Time

<Zero Follower Function>

Some sensors (ESU and SSU types) have
sensitivity variations after being used for a long
period of time.

The zero follower function uses program
manipulation to correct for sensitivity variat ions in
the zero reading.

<Sensitivity Correction

reading back to zero.

Function>

ESU type sensors have sensitivity variations after
being used for a long period of time.

The sensitivity correction function compensates for
decreasing gas sensitivity as the sensor gets older.
It periodically adjusts the span based on the
degradation pattern of the sensor.

correction

CAUTION

The sensitivity correction is just an auxiliary function. It uniformly lifts the span up based on the sensor’s
degradation pattern only. S en si tivity correction cannot consi de r th e sen siti vity v a riation o f a n i ndi vi dual

- 51 - GD-70D

Unit Replacement

1. Press the MODE key to confirm the new sensor unit and start the monitor.

sensor might have been installed by mistake.

↓

C-02

MAINTENANCE

Specification Change

might mean there is an installation error. Check the sensor installation.

ESU SSU NCU SGU OSU

OSU

(0 - 5 vol%)

OSU

(0 - 50 vol%)

Alarm delay

2­second

2-second

2-second

2­second

2­second

2­second

2­second

Suppression
value

6%FS 2 ppm

(TEOS)

6%FS

(0-100%LEL)

10%FS

0.5 vol%

0 vol%

0 vol%
Alarm type

H-HH H-HH H-HH H-HH L-LL H-HH H-HH

IRU

500ppm)

SHU

2000ppm)

Alarm delay

2­second

2-second

Suppression
value

30 ppm

200 ppm
Alarm type

H-HH

H-HH

<Calibration History/Alarm Trend History/Event History
Functions>

The detector and the sensor unit have their own history functions. To use these functions, contact RKI.

<Sensor Unit Automatic Recognition Function>

The detector can automatically recognize when a new sensor has been installed. If a replacement sensor
of the same type is installed, the detector will display a “C-01 CHG UNIT” message. If a different type
sensor is installed, the detector will display a “C-02 CHG SPEC” message.

C-01

CHG UNIT

MAINTENANCE

Displayed when a unit with the same specif ic atio n (principle, type, range, and so
on) is attached (e.g. in a regular replacement).

The following is displayed alternately if the unit that you installed has the same
or earlier date of manufacture than the one that has been replaced.

"CHG UNIT" <=> "USED SEN"

*** Check for correct installation if this message is displayed because an old

Displayed when a unit with a different specification (principle, type, range, and

CHG SPEC

so on) from the previous one is attached.

1. Press the MODE key to confirm the new specification and start the monitor.
If you did not install a sensor unit with a different specification, this message

CAUTION

If you get a “C-02” message and confirm the specification change by pressing the MODE key, the
specification of the gas detect or head is changed. The followi ng paramet ers are ch anged to thei r standa rd
settings. If you want to use nonstandard settings, set them in Maint enan ce Mode.

• Alarm setpoints (ALM P)

• Alarm delay time setting (ALM DLY)

• Suppression value (SUPPRESS)

• Alarm type (ALM TYP) ...... The OSU speci fication includes "L-LL ", "L -H" , and "H-HH".

<Standard Setting Values by Principle>

(0-

(0-

GD-70D - 52 -

PW

A1

A2

F

LCD

Detection mode

● ○ ○ ○

0.0ppm

↓

↓

1-1.ZERO

● ○ ○ ○

1- 1

MAINTENANCE

→

Zero Adjustment

6-5 About LONWORKS (LN specification)

＜Binding method＞

WARNING

≪User mode≫

Press the MODE key
for 3 seconds.

• When adjustment is completed, press the MODE key and be sure to return to detection

mode.

(When left in user mode, it automatically returns to detection mode after 10 hours.

SIH4

)

User mode

Perform the zero
adjustment.

To reissue the neuron ID, please press the MODE key in user mode for 3 seconds, return to the detection
mode, and enter the user mode again.

- 53 - GD-70D

SET

⇒P51

ZERO

Open-lLoop Sensor Functional
Block

GD-70D-LN LonWorks Diagram

Virtual Function

Block

Mandato
ry

Implementation Specific

nviReset

SNVT_lev_disc

nvoConc

SNVT_ppm_f

nvoNstate

SNVT_state

nvoAlarmS

SNVT_switch

nviComand

SNVT_str_asc

nciMaxSendTM

SNVT_time_sec

nciMinSendTM

SNVT_time_sec

nciMaxSendTl

SNVT_time_sec

nciMinSendTl

SNVT_time_sec

nvoFaultS

SNVT_switch

nvoGasName

SNVT_str_asc

nvoHertBeat
SNVT_state

nvoComand

SNVT_str_asc

nciMaxSendHB

SNVT_time_sec

GD-70D - 54 -

It is the same as the current density output.
part.

It is the same as the current density output.
Status of 16 BIT expresses measurement unit, alarm, breakdown etc.

Expression of alarm state by switch

1st & 2nd: {2.0,1}

Expression of fault condition by switch

: 9.0 = System fault

Send measured gas name and measurement unit in ASCII character

and the rest is ASCIL(00H = NULL)

Count up 8 BIT of 0 to 7 of 16 BIT
8 to 15 BIT is reserved.

7

nviReset

SNVT_lev_disc

RESET signal in case of self-latching 0:non not 0:RESET

8

nciMaxSendTM

SNVT_time_sec

1 and 2 update maximum time

9

nciMinSendTM

SNVT_time_sec

1 and 2 update minimum time

10

nciMaxSendTI

SNVT_time_sec

3 ~ 5 update maximum time

11

nciMinSendTI

SNVT_time_sec

3 ~ 5 update minimum time

5

nciMaxSendHB

SNVT_time_sec

6 update maximum time

13

nviComand

SNVT_str_asc

Command input of ASCII 30 byte

14

nvoComand

SNVT_str_asc

Command output of ASCII 30 byte

NO. Variable name Variable type Contents

1 nvoConc SNVT_ppm_f

2 nvoNstate SNVT_state

3 nvoAlarmS SNVT_switch

4 nvoFaultS SNVT_switch

5 nvoGasName SNVT_str_asc

6 nvoHertBeat SNVT_state

Floating point of 16 BIT synchronizes with the display of the detection

OFF:{0.0,0}

:{1.0,1}

1st

2nd :{1.5,1}

Normal：{0.0,0}
Fault:{X.X,1} - - X.X : 1.0 = Sensor fault

: 5.0 = Flaw rate fault
: 7.0 = Pyrolyzer fault

string.
From the beginning, we send unit after space (20H) with gas name

Count every second and count it. If it is OVER, start with 0.

You can select the transmission status with the combination of the setting point of nciMaxSendTM (8) and

nciMinSendTM (9).

・nciMaxSendTM (8) ＝ Asec nciMinSendTM (9) = Bsec －－＞ (1) and (2) transmit every Asec when

there is no VAL update. If Bsec has not elapsed since last transmission, wait until Bsec has elapsed
before sending it even if VAL is updated.

・nciMaxSendTM (8) ＝ Asec nciMinSendTM (9) = 0sec －－＞ (1) and (2) tra nsm it every Asec when

there is no VAL update. If there is an update of VAL, it will be sent immediately.

・nciMaxSendTM (8) ＝ 0sec nciMinSendTM (9) = Bsec －－＞ (1), (2) don’t transmit every Asec

when there is no VAL update. If Bsec has not elaps ed sinc e last trans mission, wait until Bsec has elapsed
before sending it even if VAL is updated.

You can select the transmission status with the combination of the setting point of nciMaxSendTI (10) and

nciMinSendTI (11).

・nciMaxSendTI (10) ＝ Asec nciMinSendTI (11) = Bsec －－＞ (3) ~ (5) transmit every Asec when

there is no VAL update. If Bsec has not elapsed since last transmission, wait until Bsec has elapsed
before sending it even if VAL is updated.

・nciMaxSendTI (10) ＝ Asec nciMinSendTI (11) = 0sec －－＞ (3) ~ (5) trans mit every Asec when

there is no VAL update. If there is an update of VAL, it will be sent immediately.

・nciMaxSendTI (10) ＝ 0sec nciMinSendTI (11) = Bsec －－＞ (3) ~ (5) don’t transmit every Asec

when there is no VAL update. If Bsec has not elaps ed sinc e last trans mission, wait until Bsec has elapsed
before sending it even if VAL is updated.

- 55 - GD-70D

You can select the transmission status with the setting point of nciMaxSendHBb(12)

・nciMaxSendHB (12) = Asec －－＞ (6) transmit every Asec.
・nciMaxSendHB (12) = 0sec －－＞ (6) don’t transmit every Asec.

It outputs to nvoComand (14) for input data of nviComand (13).

・nviComand (13) = "A1, R," －－＞ nvoComand (14) = "A1, R, ××××"
××× express 1st alarm point read value in hexadecimal.

・nviComand (13) = "A2, R," －－＞ nvoComand (14) = "A2, R, ××××"
×××× express 2nd alarm point read value in hexadecimal.

・nviComand (13) = "AD, R," －－＞ nvoComand (14) = "AD, R,××××"

×××× express Alarm delay time (mesc 10 units) read value in hexadecimal.

GD-70D - 56 -

PW

A1

A2

F

LCD

Detection Mode

● ○ ○

○

0.0ppm

↓

↓

Alarm Test Mode

pressing the ▲ or ▼ key.

● ○ ○

○

0.0ppm

MAINTENANCE

↓

↓

First Alarm

● ○ ○

○

5.0ppm

MAINTENANCE

↓

Second Alarm

alarm contact is activated.)

● ○ ○

○

10.0ppm

↓

hours.)

7

Alarm Test Mode

Alarm Test Mode generates dummy signals that imitate gas concentration signals in order to check the
alarm LED activation and the transmission to external circuits.

WARNING

• Before starting the alarm test (transmission test), prepare for false alarms by disabling alarms or

Be sure that the TEST RLY and TEST4-20 items in Maintenance Mode are set appropriately.

alerting approp ria te pe rsonnel.

• After the test is completed, do not forget to press the TEST key to return to Detection Mode.
(If the detector remains in the alarm test mode, it automatically returns to Detection Mode in ten

7-1 Alarm Test Mode

Press the TEST key for three seconds.

"TEST ON" is displayed when the alarm
contacts will activate during the alarm
test. "TEST OFF" is displayed when the
alarm contacts will not activate during
the alarm test. (The setting can be
changed in the TEST RLY menu item in
Maintenance Mode.)

Increase or decrease the reading by

When the reading reaches the first
alarm, the ALM1 lamp lights up. (When
TEST RLY is set to ON, the first alarm
contact is activated.)

SIH4

TEST OFF

TEST OFF

When the reading reaches the second
alarm, the ALM2 lamp lights up. (When
TEST RLY is set to ON, the second

GD-70D - 57 -

↓

TEST OFF

MAINTENANCE

Return to Detection Mode

Press the TEST key for 3 seconds.

GD-70D - 58 -

PW

A1

A2

F

LCD

Detection Mode

● ○ ○

○

0.0ppm

↓

User Mode

↓

1-1.ZERO

● ○ ○

○

1- 1

MAINTENANCE

Zero Adjustment

↓ ↑▼

● ○ ○

○

1- 2

MAINTENANCE

Setpoint Display

↓ ↑▼

● ○ ○

○

1- 3

MAINTENANCE

0.50

MAINTENANCE

↓ ↑▼

● ○ ○

○

1- 4

MAINTENANCE

01

MAINTENANCE

↓ ↑▼

After the adjustment is completed, do not forget to press the MODE key to return to Detection Mode.

WARNING

8-1 User Mode

8

User Mode

Press the MODE key for
three seconds.

Perform the zero
adjustment.

1-2.CONFIRM

Show the typical setpoint.

1-3.FLOW

Show the current flow rate.

SIH4

ZERO

▲

CONFIRM

▲

FLOW

→

SET

→

SET

→

SET

⇒P62

⇒P63

L/M

▲

1-4.ADDRESS

Show the address.
(for GD-70D-NT)

GD-70D - 59 -

ADDRESS

▲

SET

→

ADDRESS

● ○ ○

○

1- 5

MAINTENANCE

01234

MAINTENANCE

↓ ↑▼

● ○ ○

○

1- 6

MAINTENANCE

01234

MAINTENANCE

↓ ↑▼

(for GD-70D-NT)

● ○ ○

○

1- 7

MAINTENANCE

01234

MAINTENANCE

↓ ↑▼

1-8.M MODE

● ○ ○

○

1- 8

MAINTENANCE

See Maintenance

↓ ↑▼

To 1-1.ZERO

【

1-7. NET VER

(NT specification)

● ○ ○

○

1- 7

→

01234

↓↑

1-8.COM SET

confirm the value.

● ○ ○

○

1- 8

⇔

A

↓↑

｜↑

A: Analog transmission

E

MAINTENANCE

▲↓↑▼

EA

MAINTENANCE

1-5.70D VER

Show the program version
of the main unit.

1-6.UNIT VER

Show the program version
of the installed sensor unit.

1-7.NET VER

Show the program version
of the communication
function.

Enter Maintenance Mode.

70D VER

▲

UNIT VER

▲

NET VER

▲

M MODE

→

SET

→

SET

→

SET

→

SET

56AB

56AB

----

Mode on page 65.

In case of GD-70D-EA】

Show the program
version of the
communication
function.

Set communication
output.
Press the ▲ or ▼ key
to select the
communication
output, and then press
the SET key to

E: Ethernet
EA: Ethernet and analog
transmission

GD-70D - 60 -

▲

NET VER

MAINTENANCE

▲

COM SET

MAINTENANCE

｜｜

▲｜｜▼

SET

----

MAINTENANCE

▼

SET

COM SET

MAINTENANCE

▲

▼

COM SET

COM SET

1-9. M MODE

○ ○ ○

1- 9

MAINTENANCE

→

See Maintenance

↓↑

To 1-1. ZERO

Switch to the regular
maintenance mode.

M MODE

▲

▼

SET

Mode on page 65.

NOTE

• Communication output setting 1-8 (COM SET) is displayed only for EA specification.

• In EA specification, if only analog transmission is used (Ethernet is not used), if the communication

output setting is set to A, Communication Abnormalities E-6 does not occur even if an Ethernet cable
is not connected.

- 61 - GD-70D

PW

A1

A2

F

LCD

From Detection Mode, press the

● ○ ○

○

0.0ppm

↓

↓

1-1.ZERO

● ○ ○

○

1- 1

MAINTENANCE

↓

↓

Current Concentration Value

● ○ ○

○

1.1ppm

MAINTENANCE

↓

↓

Zero Adjustment Completed

● ○ ○

○

0.0ppm

MAINTENANCE

↓

Return to 1-1.ZERO

* If the zero adjustment fail s .

● ○ ○

○

0.0ppm

MAINTENANCE

↓

Return to 1-1.ZERO

<Zero Adjustment "1-1">

This is used to perform the zero adjustment. Before starting the zero adjustment, let the detector draw
fresh air or zero air until the reading is stable.
For oxygen units, "1-1" is called the span adjustment instead of the zero adjustment. In this case, fresh air
or zero air must be applied to the detector to ensure the reading is 20.9 vol%. For information on the span
adjustment, see Maintenance on page 86.

Zero Adjustment

MODE key for three seconds.

SIH4

Press the SET key.

ZERO

Display

Press the SET key to perform the
zero adjustment.

The menu returns to 1-1.ZERO
automatically.

ZERO SET

ZERO OK

ZERO NG

GD-70D - 62 -

PW

A1

A2

F

LCD

From Detection Mode, press the

● ○ ○

○

0.0ppm

↓

↓

1-1.ZERO

● ○ ○

○

1- 1

MAINTENANCE

↓

↓

1-2.CONFIRM

● ○ ○

○

1- 2

MAINTENANCE

↓

First Alarm Setpoint

● ○ ○

○

5.0ppm

MAINTENANCE

↓ ↑▼

Second Alarm Setpoint

● ○ ○

○

10.0ppm

MAINTENANCE

↓ ↑▼

Alarm Delay Time (seconds)

● ○ ○

○

2

MAINTENANCE

↓ ↑▼

Zero Suppression Value

● ○ ○

○

0.9ppm

MAINTENANCE

↓ ↑▼

Zero Follower ON/OFF

● ○ ○

○

ON

MAINTENANCE

↓ ↑▼

<Setpoint Indicator "1-2">

Use this menu item to check important setpoints. Setpoints cannot be changed in User Mode.

Setpoint Display

MODE key for three seconds.

SIH4

Press the ▼ key.

ZERO

Press the SET key.

CONFIRM

↓

AL 1

▲

AL 2

▲

ALM DLY

▲

SUPPRESS

(If ESU or SSU sensor installed)

- 63 - GD-70D

▲

ZERO F

▲

Sensitivity Correction ON/OFF

● ○ ○

○

OFF

MAINTENANCE

↓ ↑▼

To First Alarm

Setpoint Indicator

(If ESU sensor installed)

S ASSIST

▲

GD-70D - 64 -

Maintenance Mode Item

LCD Display

Details

Gas Introduction Display

2-0 GAS TEST

Perform the gas introduction test in the regular
maintenance mode.

Zero Adjustment

2-1 ZERO

Perform the zero adjustment.
Span Adjustment

2-2 SPAN

Perform the span adjustment.
Last Calibrated Date

2-3 LAST CAL

Show the last calibrated date.

Bias Voltage

2-4 BIAS

Show the bias voltage.

Flow Rate Setting (adjusted

2-5 DEF FLOW

Set the flow sensor with the flow rate at 0.5 L/min.

Pump Ratio/Flow Rate

2-6 FLOW

Show the output and flow rate of the current pump.

Detector Temperature

2-7 TEMP

Show the current temperature of the installation
environment.

Suggested Warm-up

2-8 WARMTIME

Show the suggested warm-u p com plet ion for SGU type

Environmental Setting 1

2-9 SETTING1

Operation settings

Fault alarm test (F TEST) ⇒P73

(If the detector remains in Maintenance Mode, it automatically returns to Detection Mode in ten hours.)

9

Maintenan ce Mo de

WARNING

After the adjustment is completed, do not forget to press the MODE key to return to Detection Mode.

⇒P86Error! Bookmark
not defined.

⇒P86

(Element Voltage)

to 0.5 L/min)

⇒P110

Indicator

⇒P110

Completion Date/Time

⇒P70

(2-4 E VOLT)

(Show the element voltage.)

sensors.

• INHIBIT setting (INHIBIT)

• Alarm value setting (ALM P) ⇒P71

• Alarm delay time setting (ALM DLY)

• Pump stop (MAINTE)

•

GD-70D - 65 -

Maintenance Mode Item

LCD Display

Details

Environmental Setting 2

2-10 SETTING2

Function settings

• Pump drive level diagnosis ON/OFF setting (PUMP CK)

Pyrolyzer Data Display

2-11 PL DATA

When the pyrolyzer unit (PLU-70) is used, a variety of
(See the operating manual for PLU-70)

Fault Investigation

2-12 FAULT

Not used

Factory Mode Switching

2-13 F MODE

Not used

⇒P74

• Address setting (ADDRESS)

• Date/Time setting (DAY TIME) ⇒P79

• Zero suppression value setting (SUPPRESS)

• Zero suppression type setting (SUP TYPE)

• Alarm test mode contact setting (TEST RLY)

• Alarm test mode external output setting (TEST4-20)

• Energized/De-energized setting (RLY PTRN)

⇒P81

• Alarm type setting (ALM TYP)

• Alarm activation setting (ALM PTRN)

• Alarm value limiter setting (AL LIMIT)

• Fault activation setting (FLT PTRN)

• Flow rate auto-adjustment setting (AT FLOW)

• Zero follower ON/OFF setting (ZERO F)

• 24 hours zero follower ON/OFF setting (ZERO 24F)

• Sensitivity correction ON/OFF setting (S ASSIST)

• External output in maintenance mode setting (MNT OUT)

• External output adjustment (MA 4-20)

• Backlight setting (BK LIGHT)

• ETHERNET setting (ETHERNET)

pyrolyzer data is displayed.

GD-70D - 66 -

PW

A1

A2

F

LCD

From Detection Mode, press

● ○ ○

○

0.0ppm

↓

↓

screen is item 1-9.)

● ○ ○

○

1- 8

↓

↓

User Mode

● ○ ○

○

1- 8

MAINTENANCE

↓

↓

Then press and hold the SET

● ○ ○

○

- - - -

MAINTENANCE

↓

↓

2-0.GAS TEST

● ○ ○

○

2- 0

MAINTENANCE

0.2ppm

MAINTENANCE

↓

0.2ppm

MAINTENANCE

2-1.ZERO

● ○ ○

○

2- 1

MAINTENANCE

Zero Adjustment

↓ ↑▼

2-2.SPAN

● ○ ○

○

2- 2

MAINTENANCE

Span Adjustment

↓ ↑▼

PW: POWER

F: FAULT

●: Lamp on

Maintenance Mode

and hold the MODE key for
three seconds.

1-8.M MODE

Press the ▲ key until the
Maintenance Mode screen
displays. (For GD-70D-EA
units, the Maintenance Mode

In "1-8.M MODE", press the
SET key.

SIH4

M MODE

MAINTENANCE

M MODE

A1: ALM1
A2: ALM2

○: Lamp off

key again for three seconds.

Maintenance Mode

Perform a test with the gas.
The reading changes and the
alarm lamp lights up, but the
alarm contacts are not
activated and the 4-20 mA
output does not track the
changes.

Perform a zero adjustment.

M MODE

GAS TEST

▲↓ ↑▼

ZERO

→

SET

→

SET

GAS TEST

(Alternate Display)↑

SIH4

⇒P86

Perform a span adjustment.

- 67 - GD-70D

▲

SPAN

▲

→

SET

⇒P86

2-3.LAST CAL

● ○ ○

○

2- 3

MAINTENANCE

12:00

MAINTENANCE

↓ ↑▼

2-4.BIAS

● ○ ○

○

2- 4

MAINTENANCE

0 mV

MAINTENANCE

↓ ↑▼

2-5.DEF FLOW

cancel this menu.)

● ○ ○

○

2- 5

MAINTENANCE

⇔

1000

MAINTENANCE

2-6.FLOW

● ○ ○

○

2- 6

MAINTENANCE

⇔

50 %

MAINTENANCE

↓ ↑▼

2-7.TEMP

● ○ ○

○

2- 7

25.0 °C

MAINTENANCE

↓ ↑▼

2-8. WARMTIME

● ○ ○

○

2- 8

MAINTENANCE

12:00

↓ ↑▼

2-9. SETTING1

● ○ ○

○

2- 9

MAINTENANCE

Environmental

↓ ↑▼

→

Show the most recent
calibration date.

Show the bias voltage "BIAS"
of electrochemical type (ESU)
or the element voltage
"EVOLT" of semiconductor
type (SGU) and hot-wire
semiconductor type (SHU).

LAST CAL

▲

BIAS

▲

SET

2009.01.01

→

SET

BIAS

Set the flow rate to the default
value when the flow sensor is
replaced, etc.
Normally , this is not used
because the detector has
already been adjusted.
On the other hand, if the flow
meter is set at other than the
specified flow rate, gases
cannot be detected properly
due to an incorrect flow rate.
(Press the MODE key to

Show the output and flow rate
of the current pump.

Show the temperature of the
detector.

DEF FLOW

▲↓ ↑▼

FLOW

▲

TEMP

MAINTENANCE

SET

DEF FLOW

SET

0.50 L/M

→

SET

TEMP

GD-70D - 68 -

Show the suggested warm-up
completion date/time for
semiconductor type (SGU),
and hot-wire semiconductor
type (SHU) which requires a
long warm-up time.

Enter the environmental
setting 1 menu.

▲

WARMTIM

E

▲

SETTING1

▲

→

SET

→

SET

2009.01.01

MAINTENANCE

Setting 1 ⇒P71

2-10.SETTING2

● ○ ○

○

2-10

MAINTENANCE

Environmental

↓ ↑▼

2-11.PL DATA

● ○ ○

○

2-11

For information on

Manual".

↓ ↑▼

2-12.FAULT

● ○ ○

○

2-12

MAINTENANCE

↓ ↑▼

2-13.F MODE

● ○ ○

○

2-13

MAINTENANCE

↓ ↑▼

To 2-0.GAS TEST

Enter the environmental
setting 2 menu.

Show the pyrolyzer data
when the pyrolyzer unit (PLU-

70) is used.

This is used (by the
manufacturer) to investigate
and analyze the causes of
faults. This is not used by the
user.

SETTING2

▲

PL DATA

MAINTENANCE

▲

FAULT

▲

→

SET

→

SET

Setting 2 ⇒P74

Pyrolyzer Data
Display, see "PLU­70 Operating

Changes to the factory mode.
This is not used by the user.

F MODE

▲

- 69 - GD-70D

PW

A1

A2

F

LCD

From Detection Mode, press

● ○ ○

○

0.0ppm

↓

↓

1-8.M MODE

screen is item 1-9.)

● ○ ○

○

1- 8

↓

↓

User Mode

● ○ ○

○

1- 8

MAINTENANCE

↓

↓

Then press and hold the SET

● ○ ○

○

- - - -

MAINTENANCE

↓

↓

2-0.GAS TEST

● ○ ○

○

2- 0

↓

↓

2-9.SETTING1

Press the SET key.

● ○ ○

○

2- 9

↓

↓

SET 0.INHIBIT

● ○ ○

○

SET 0

MAINTENANCE

⇔

OFF

MAINTENANCE

↓↑

ON

INHIBIT

9-1 Environmental Setting 1 "2-9"

The Environmental Setting 1 menu allows you to view and/or change operation settings.

Environmental Setting 1

and hold the MODE key for
three seconds.

SIH4

Press the ▲ key until the
Maintenance Mode screen
displays. (For GD-70D-EA
units, the Maintenance Mode

In "1-8.M MODE", press the
SET key.

M MODE

MAINTENANCE

M MODE

key again for three seconds.

The first item in Maintenance
Mode will display.

Press the ▼ key until the
SETTING1 screen displays.

Select either ON or OFF, and
then press the SET key to
confirm the selection.
When ON is selected, the
message INHIBIT is
displayed on the LCD. Any
alarms triggered in Detection
Mode are not communicated
to the relays or to the 4-20
mA output.

M MODE

GAS TEST

MAINTENANCE

SETTING1

MAINTENANCE

SET

INHIBIT

▲↓ ↑▼

INHIBIT

▲

▼

INHIBIT

MAINTENANCE

GD-70D - 70 -

SET 1.ALM P

● ○ ○

○

SET 1

MAINTENANCE

Alarm Value Setting

↓ ↑▼

SET 2.ALM DLY

● ○ ○

○

SET 2

MAINTENANCE

⇔

2

MAINTENANCE

↓ ↑▼

SET 3. MAINTE

and restart the pump.)

● ○ ○

○

SET 3

MAINTENANCE

⇔

-----

MAINTENANCE

Pump Stop

SET 4.F TEST

● ○ ○

○

SET 4

MAINTENANCE

⇔

Fault Alarm Test

↓ ↑

To

SET 0.INHIBIT Setting

PW

A1

A2

F

LCD

From Detection Mode, press and hold

● ○ ○

○

0.0ppm

↓

↓

1-8.M MODE

item 1-9.)

● ○ ○

○

1- 8

↓

↓

User Mode

● ○ ○

○

1- 8

MAINTENANCE

↓

↓

Change the alarm setpoints.

Set the alarm delay time. Use
the ▲ or ▼ key to change the
value (in seconds), and then
press the SET key to confirm
the value.

This is used to stop the pump
(useful for pump
replacement).
Press the SET key to stop the
pump. Press the SET key
again to restart the pump.
(You can also press the
MODE key to exit this menu

ALM P

▲

ALM DLY

▲

MAINTE

▲

↓ ↑▼

⇔

SET

SET

SET

⇒P71

ALM DLY

MAINTE

(Drive Sound Stop)

Perform a fault alarm test.

F TEST

▲

▼

9-2 Alarm Value Setting "2-9" - "SET 1"

Alarm Value Setting

the MODE key for three seconds.

SIH4

Press the ▲ key until the Maintenance
Mode screen displays. (For GD-70D-EA
units, the Maintenance Mode screen is

M MODE

MAINTENANCE

SET

⇒P73

In "1-8.M MODE", press the SET key.

- 71 - GD-70D

M MODE

Then press and hold the SET key again

● ○ ○

○

- - - -

MAINTENANCE

↓

↓

2-0.GAS TEST

● ○ ○

○

2- 0

MAINTENANCE

↓

↓

2-9. SETTING1

Press the SET key.

● ○ ○

○

2- 9

↓

↓

● ○ ○

○

SET 1

MAINTENANCE

↓

↓

SET 1.ALM P

● ○ ○

○

SET 1

MAINTENANCE

↓

↓

First Alarm Value Setting

this menu.)

● ○ ○

○

5.0ppm

MAINTENANCE

↓

↓

Second Alarm Value Setting

this menu.)

● ○ ○

○

10.0ppm

MAINTENANCE

↓

Return to

SET 1.ALM P

for three seconds.

M MODE

The first item in Maintenance Mode will
display.

Press the ▲ key until the SETTING1
screen displays.

GAS TEST

SETTING1

MAINTENANCE

SET 1.ALM P

Press the ▼ key until the ALM P screen
displays.

Press the SET key.

Use the ▲ or ▼ key to change the
setpoint. Press the SET key to confirm
the value. (Press the MODE key to skip

Use the ▲ or ▼ key to change the
setpoint. Press the SET key to confirm
the value. (Press the MODE key to skip

ALM P

ALM P

AL 1

AL 2

GD-70D - 72 -

PW

A1

A2

F

LCD

From Detection Mode, press and hold

● ○ ○

○

0.0ppm

↓

↓

1-8.M MODE

item 1-9.)

● ○ ○

○

1- 8

↓

↓

User Mode

● ○ ○

○

1- 8

MAINTENANCE

↓

↓

Then press and hold the SET key again

● ○ ○

○

- - - -

MAINTENANCE

↓

↓

2-0.GAS TEST

● ○ ○

○

2- 0

MAINTENANCE

↓

↓

Press the SET key.

● ○ ○

○

2- 9

↓

↓

● ○ ○

○

SET 1

MAINTENANCE

↓

↓

SET 4.F TEST

● ○ ○

○

SET 4

MAINTENANCE

↓

↓

9-3 Fault Alarm Test "2-9" - "SET 4"

the MODE key for three seconds.

SIH4

Press the ▲ key until the Maintenance
Mode screen displays. (For GD-70D-EA
units, the Maintenance Mode screen is

In "1-8.M MODE", press the SET key.

M MODE

MAINTENANCE

M MODE

for three seconds.

The first item in Maintenance Mode will
display.

2-9. SETTING1

Press the ▲ key until the SETTING1
screen displays.

SET 1.ALM P

Press the ▼ key until the F TEST
screen displays.

M MODE

GAS TEST

SETTING1

MAINTENANCE

F TEST

Press the SET key.

- 73 - GD-70D

F TEST

Fault Test ON/OFF

● ○ ○

○

OFF

MAINTENANCE

↓ ↑

● ○ ○

●

ON

MAINTENANCE

PW

A1

A2

F

LCD

From Detection Mode, press

● ○ ○

○

0.0ppm

↓

↓

1-8.M MODE

screen is item 1-9.)

● ○ ○

○

1- 8

↓

↓

User Mode

● ○ ○

○

1- 8

MAINTENANCE

↓

↓

Then press and hold the SET

● ○ ○

○

- - - -

MAINTENANCE

↓

↓

With ON displayed, press the SET key to
activate the fault alarm.
With OFF displayed, press the SET key
to deactivate the fault alarm.
(You can also press the MODE key to
cancel this menu and go back to the
original state.)

F TEST

▲

▼

F TEST

WARNING

Because the contact ( fault ) can be activate d only by a fault alar m test in Mainte nance Mode , be care ful to
perform the test. The fault alarm test cannot be performed dur ing inhibi t.

9-4 Environmental Setting 2 "2-10"

The Environmental Setting 2 menu allows you to view and/or change function settings. (* It is
recommended that any setting changes made be recorded in a log.)

Settings found in the Environmental Setting 2 menu are factory set and do not normally need to be
changed. Be careful not to change these settings by mistake.

Environmental Setting 2

and hold the MODE key for
three seconds.

SIH4

Press the ▲ key until the
Maintenance Mode screen
displays. (For GD-70D-EA
units, the Maintenance Mode

M MODE

MAINTENANCE

In "1-8.M MODE", press the
SET key.

key again for three seconds.

GD-70D - 74 -

M MODE

M MODE

2-0.GAS TEST

● ○ ○

○

2- 0

MAINTENANCE

↓

↓

Press the SET key.

● ○ ○

○

2- 10

↓

↓

SET 0. ADDRESS

● ○ ○

○

SET 0

MAINTENANCE

⇔

01

MAINTENANCE

↓ ↑

SET 1.DAY TIME

● ○ ○

○

SET 1

MAINTENANCE

⇔

Date/Time Setting

↓ ↑▼

SET 2.SUPPRESS

● ○ ○

○

SET 2

MAINTENANCE

⇔

0.9ppm

MAINTENANCE

↓ ↑

SET 3. SUP TYPE

● ○ ○

○

SET 3

MAINTENANCE

⇔

CUT

MAINTENANCE

↓↑

SLOPE

MAINTENANCE

SET 4. TEST RLY

● ○ ○

○

SET 4

MAINTENANCE

⇔

OFF

MAINTENANCE

↓↑

ON

MAINTENANCE

The first item in Maintenance
Mode will display.

2-10. SETTING2

Press the ▲ key until the
SETTING2 screen displays.

Set the address for GD-70D­NT units.
Select the number by
pressing the ▲ or ▼ key,
and then press the SET key
to confirm the address.

Set the date/time of the main
unit.

GAS TEST

SETTING2

MAINTENANCE

SET

ADDRESS

▲

▼

SET

ADDRESS

⇒P79

DAY TIME

Set the suppression value.
Select the number by
pressing the ▲ or ▼ key,
and then press the SET key
to confirm the value.

Set the suppression system.
Select either CUT or SLOPE,
and then press the SET key
to confirm the selection.
When CUT is selected, the
display will jump up to the
gas reading as soon as it
exceeds the suppression
value. When SLOPE is
selected, the display will
ramp up to the gas reading
once it exceeds the
suppression value.

Set the contact activation for
an alarm test.
Select either ON or OFF, and
then press the SET key to
confirm the selection.
When ON is selected, the
contact can be activated
even during an alarm test.

▲

SET

SUPPRESS

▲

▼

SET

SUP TYPE

▲↓ ↑▼

SET

TEST RLY

▲

↓ ↑▼

SUPPRESS

SUP TYPE

▲

SUP TYPE

TEST RLY

▲

TEST RLY

▼

▼

- 75 - GD-70D

SET 5.TEST4-20

● ○ ○

○

SET 5

MAINTENANCE

⇔

ON

MAINTENANCE

↓↑

OFF

MAINTENANCE

SET 6.RLY PTRN

● ○ ○

○

SET 6

MAINTENANCE

⇔

Energized/De-

↓ ↑▼

SET 7.ALM TYPE

● ○ ○

○

SET 7

MAINTENANCE

⇔

L-LL

MAINTENANCE

↓↑

L-H

MAINTENANCE

↓↑

H-HH

MAINTENANCE

SET 8.ALM PTRN

● ○ ○

○

SET 8

MAINTENANCE

↓ ↑

SET 9.AL LIMIT

● ○ ○

○

SET 9

MAINTENANCE

↓ ↑

Set the external output for an
alarm test.
Select either ON or OFF, and
then press the SET key to
confirm the selection.
When ON is selected, the
output follows the reading
even during an alarm test.
When OFF is selected, the
output is what it was right
before entering alarm test
mode.
* When 4 - 20 mA is selected
in SET 15, the 4-20 mA
output is generated during an
alarm test regardless of this
TEST4-20 setting.

Select either energized/de­energized for the contact.
(De-energized by default)

TEST4-20

▲↓ ↑▼

RLY PTRN

SET

SET

TEST4-20

▲

TEST4-20

Energized Contact
Setting

⇒P81

▼

Set the alarm type.
When the galvanic cell type
(OSU) is installed, you can
select either L-LL (both
alarms decreasing), L-H
(alarm 1 decreasing, alarm 2
increasing), or H-HH (both
alarms increasing).

This is a setting screen of the
gas alarm activation. Do not
change the setting when the
detector is used in a normal
way, because it determines
how the detector functions.
(Auto-reset setting: "nL" by
default)

▲

ALM TYPE

▲↓ ↑▼

ALM PTRN

▲

▼

SET

ALM TYPE

ALM TYPE

ALM TYPE

▲

▲

▼

▼

GD-70D - 76 -

This is a setting screen of the
alarm value limiter. Do not
change the setting when the
detector is used in a normal
way.
(ON by default)

AL LIMIT

▲

▼

SET 10. FLT PTRN

● ○ ○

○

SET 10

MAINTENANCE

SET 11.AT FLOW

● ○ ○

○

SET 11

MAINTENANCE

⇔

ON

MAINTENANCE

↓↑

OFF

MAINTENANCE

SET 12. ZERO F

● ○ ○

○

SET 12

MAINTENANCE

⇔

ON

MAINTENANCE

↓↑

OFF

MAINTENANCE

SET 13.ZERO 24F

(ON by default)

● ○ ○

○

SET 13

MAINTENANCE

SET 14.S ASSIST

● ○ ○

○

SET 14

MAINTENANCE

⇔

ON

MAINTENANCE

↓↑

OFF

MAINTENANCE

This is a setting screen of the
fault alarm activation. Do not
change the setting when the
detector is used in a normal
way, because it determines
how the detector functions.
(Auto-reset setting: "nL" by
default)

Set the flow rate auto­adjustment.
Select either ON or OFF, and
then press the SET key to
confirm the selection.
When ON is selected, the
flow rate auto-adjustment is
activated.

Set the zero follower when
the electrochemical type
(ESU), pyrolysis-particle type
(SSU), new ceramic type
(NCU), or NDIR type (IRU)
sensor is installed.
Select either ON or OFF, and
then press the SET key to
confirm the selection.
When ON is selected, the
zero follower function is
activated.
* When SSU is installed, you
must select ON.

FLT PTRN

▲↓ ↑▼

AT FLOW

▲↓ ↑▼

ZERO F

▲↓ ↑▼

SET

SET

AT FLOW

▲

▼

AT FLOW

ZERO F

▲

▼

ZERO F

- 77 - GD-70D

This is a supplemental
setting screen for the above
zero follower function. (A
setting to determine whether
the first-24-hour zero follower
will be performed after the
power is turned on.)
Do not change the setting
when the detector is used in
a normal way.

Set the sensitivity correction
when the electrochemical
type (ESU) is installed.
Select either ON or OFF, and
then press the SET key to
confirm the selection.
When ON is selected, the
sensitivity correction function
is activated.

ZERO 24F

▲↓ ↑▼

S ASSIST

▲↓ ↑▼

SET

S ASSIST

▲

▼

S ASSIST

SET 15. MNT OUT

● ○ ○

○

SET 15

MAINTENANCE

⇔

2.5mA

MAINTENANCE

↓↑

4.0mA

MAINTENANCE

↓↑

HOLD

MAINTENANCE

↓↑

4-20mA

MAINTENANCE

SET 16.MA 4-20

● ○ ○

○

SET 16

MAINTENANCE

⇔

100%

MAINTENANCE

↓

100%

MAINTENANCE

SET 17.BK LIGHT

● ○ ○

○

SET 17

MAINTENANCE

⇔

ON

MAINTENANCE

↓↑

SAVE

MAINTENANCE

SET 18. ETHERNET

● ○ ○

○

SET 18

MAINTENANCE

↓ ↑

Set the external output for
Maintenance Mode.
Select either 2.5 mA, 4.0
mA, HOLD (previous value),
or 4 - 20 mA (tracks display
value), and then press the
SET key to confirm the
selection.

MNT OUT

SET

MNT OUT

▲

▼

MNT OUT

↓ ↑▼

▲

▲

▼

MNT OUT

▲

▼

MNT OUT

Adjust the external output (4 ­20 mA).
Adjust the output (%) by
pressing the ▲ or ▼ key,
and then press the SET key
to confirm the value.
(It must be adjusted to the
upper unit or the ammeter.)
After adjustment of 4 mA is
completed, perform the
adjustment of 20 mA.
(Press the MODE key to exit
menu after entering.)

Set the backlight.
Select either ON or SAVE,
and then press the SET key
to confirm the selection.
When ON is selected, the
backlight is on continuously.
When SAVE is selected, the
backlight is normally off, but
turns on during an operation
or event.

SET

MA 4-20

4MA ADJ

▲↓ ↑▼

SET

BK LIGHT

▲↓ ↑▼

20MA ADJ

BK LIGHT

BK LIGHT

▲

▼

This is a setting screen of the
ETHERNET setting. This is
not used for the detector.

GD-70D - 78 -

ETHERNET

▲

▼

SET 19.PUMP CK

pressure, etc.)

● ○ ○

○

SET 19

MAINTENANCE

⇔

ON

MAINTENANCE

↓↑

OFF

MAINTENANCE

To

SET 0. ADDRESS

PW

A1

A2

F

LCD

From Detection Mode, press and hold

● ○ ○

○

0.0ppm

↓

↓

1-8.M MODE

item 1-9.)

● ○ ○

○

1- 8

↓

↓

User Mode

● ○ ○

○

1- 8

MAINTENANCE

↓

↓

Then press and hold the SET key again

● ○ ○

○

- - - -

MAINTENANCE

↓

↓

2-0.GAS TEST

● ○ ○

○

2- 0

MAINTENANCE

↓

↓

2-10. SETTING2

Press the SET key.

● ○ ○

○

2- 10

Set the pump drive level
diagnosis.
Select either ON or OFF, and
then press the SET key to
confirm the selection.
When ON is selected, the
message "FLOW" is
displayed if the flow rate is
sufficient even though the
pump drive level is low. (A
function to check the
conditions for applying

PUMP CK

▲↓ ↑▼

9-5 Date/Time Setting "2-10" - "SET 1"

Date/Time Setting

the MODE key for three seconds.

SET

PUMP CK

▲

▼

PUMP CK

Press the ▲ key until the Maintenance
Mode screen displays. (For GD-70D-EA
units, the Maintenance Mode screen is

In "1-8.M MODE", press the SET key.

for three seconds.

SIH4

M MODE

MAINTENANCE

M MODE

M MODE

The first item in Maintenance Mode will
display.

Press the ▲ key until the SETTING2
screen displays.

- 79 - GD-70D

GAS TEST

SETTING2

MAINTENANCE

↓

↓

SET 1.DAY TIME

● ○ ○

○

SET 1

MAINTENANCE

↓

↓

Date/Time Setting Display

● ○ ○

○

12:00

MAINTENANCE

↓

Year Setting

● ○ ○

○

12:00

MAINTENANCE

↓

Month Setting

● ○ ○

○

12:00

MAINTENANCE

↓

Date Setting

● ○ ○

○

12:00

MAINTENANCE

↓

Hour Setting

● ○ ○

○

12:00

MAINTENANCE

↓

Minute Setting

● ○ ○

○

12:00

MAINTENANCE

↓

Return to

SET 1.DAY TIME

Press the SET key.

DAY TIME

Press the SET key.

2009.01.01

Select the number by pressing the ▲ or
▼ key, and then press the SET key to
confirm the value.

2009.01.01

Select the number by pressing the ▲ or
▼ key, and then press the SET key to
confirm the value.

Select the number by pressing the ▲ or
▼ key, and then press the SET key to
confirm the value.

Select the number by pressing the ▲ or
▼ key, and then press the SET key to
confirm the value.

Select the number by pressing the ▲ or
▼ key, and then press the SET key to
confirm the value.

2009.01.01

2009.01.01

2009.01.01

2009.01.01

* In the Date/Time Setting mode, press the MODE key to cancel the changes and go back to the previous
setting.

GD-70D - 80 -

PW

A1

A2

F

LCD

From Detection Mode, press

● ○ ○

○

0.0ppm

↓

↓

1-8.M MODE

Mode screen is item 1-9.)

● ○ ○

○

1- 8

↓

↓

User Mode

● ○ ○

○

1- 8

MAINTENANCE

↓

↓

Then press and hold the

● ○ ○

○

- - - -

MAINTENANCE

↓

↓

2-0.GAS TEST

● ○ ○

○

2- 0

MAINTENANCE

↓

↓

2-10. SETTING2

Press the SET key.

● ○ ○

○

2- 10

↓

↓

SET 6. RLY PTRN

● ○ ○

○

SET 6

MAINTENANCE

↓

↓

SET 6. RLY PTRN

● ○ ○

○

SET 6

MAINTENANCE

↓

↓

9-6 Energized/De-Energized Contact Setting "2-10" ­"SET 6"

and hold the MODE key for
three seconds.

SIH4

Press the ▲ key until the
Maintenance Mode screen
displays. (For GD-70D-EA
units, the Maintenance

In "1-8.M MOD E ", press the
SET key.

M MODE

MAINTENANCE

M MODE

SET key again for three
seconds.

The first item in
Maintenance Mode will
display.

Press the ▲ key until the
SETTING2 screen displays.

Press the ▲ key until the
RLY PTRN screen displays.

M MODE

GAS TEST

SETTING2

MAINTENANCE

RLY PTRN

Press the SET key.

- 81 - GD-70D

RLY PTRN

First Alarm Contact

Factory setting is nd.

● ○ ○

○

nd

MAINTENANCE

⇔

nE

MAINTENANCE

↓

↓

Second Alarm Contact

Factory setting is nd.

● ○ ○

○

nd

MAINTENANCE

⇔

nE

MAINTENANCE

↓

↓

Fault Alarm Contact

Factory setting is nd.

● ○ ○

○

nd

MAINTENANCE

⇔

nE

MAINTENANCE

↓

Return to

PTRN

Setting

Select either nd(De­Energized)/nE(Energized),
and then press the SET key
to confirm the selection.
(Press the MODE key to
skip this menu.)

Setting

Select either nd (De­Energized)/nE (Energized),
and then press the SET key
to confirm the selection.
(Press the MODE key to
skip this menu.)

Setting

Select either nd (De­Energized)/nE (Energized),
and then press the SET key
to confirm the selection.
(Press the MODE key to
skip this menu.)

AL1 RLY

AL2 RLY

FLT RLY

▲/▼

AL1 RLY

▲/▼

AL2 RLY

▲/▼

FLT RLY

NOTE

When De-energized (nd) is selected, the relay is energized and activated during an alarm condition (de­energized during normal operation).

• When the alarm contacts are configured as normally open, the contacts are open during normal
operation and closed during an alarm condition.

• When the alarm contacts are configured as normally closed, the contacts are closed during normal
operation and open during an alarm condition.

When Energized (nE) is selected, the relay is energized during normal operation (de-energized dur ing an
alarm condition).

• When the alarm contacts are configured as normally open, the contacts are closed during normal
operation and open during an alarm condition. They close if the power is turned OFF.

• When the alarm contacts are configured as normally closed, the contacts are open during normal
operation and closed during an alarm condition.

SET 6. RLY

GD-70D - 82 -

PW

A1

A2 F LCD

From Detection Mode, press

● ○ ○

○

0.0ppm

↓

↓

1-8.M MODE

Mode screen is item 1-9.)

● ○ ○

○

1- 8

↓

↓

User Mode

● ○ ○

○

1- 8

MAINTENANCE

↓

↓

Then press and hold the

● ○ ○

○

- - - -

MAINTENANCE

↓

↓

2-0.GAS TEST

● ○ ○

○

2- 0

MAINTENANCE

↓

↓

2-10. SETTING2

Press the SET key.

● ○ ○

○

2- 10

↓

↓

SET 18. RLY PTRN

● ○ ○

○

SET 18

MAINTENANCE

↓

↓

SET 18. ETHERNET

● ○ ○

○

SET 18

MAINTENANCE

↓

↓

9-7 ETHERNET Setting "2-10" - "SET 18"

<ETHERNET Setting>

and hold the MODE key for
three seconds.

SIH4

Press the ▲ key until the
Maintenance Mode screen
displays. (For GD-70D-EA
units, the Maintenance

In "1-8.M MOD E ", press the
SET key.

M MODE

MAINTENANCE

M MODE

SET key again for three
seconds.

The first item in
Maintenance Mode will
display.

Press the ▲ key until the
SETTING2 screen displays.

Press the ▲ key until the
ETHERNET screen
displays.

M MODE

GAS TEST

SETTING2

MAINTENANCE

ETHERNET

Press SET key.

- 83 - GD-70D

ETHERNET

MAC Address Check

● ○ ○

○

00

MAINTENANCE

↓↑

(MAC2 -

MAC6)

↓↑

IP Address Setting

by one in the same way.

● ○ ○ ○

0

MAINTENANCE

⇔

255

MAINTENANCE

↓↑

(IP2 - IP4)

↓↑

Subnet Mask Setting

way.

● ○ ○

○

0

MAINTENANCE

⇔

255

MAINTENANCE

↓↑

(SUB2 -

↓↑

Default Gateway Setting

same way.

● ○ ○

○

0

MAINTENANCE

⇔

255

MAINTENANCE

↓↑

(DEF2 - DEF4)

There are MAC
addresses from MAC1
to MAC6. Select one
using ▲ and ▼ keys
and display them one by
one in the same way.
* MAC addresses are
fixed values unique to
the unit.

Change the value by
pressing the ▲ or ▼
key, and then press the
SET key to confirm the
value.

There are IP addresses
from IP1 to IP4. Select
one using ▲ and ▼
keys and set them one

MAC 1

▲

▲

▼

▼

IP 1

▲

▼

SET

IP 1

Change the value by
pressing the ▲ or ▼
key, and then press the
SET key to confirm the
value.

There are subnet masks
from SUB1 to SUB4.
Select one using ▲ and
▼ keys and set them
one by one in the same

Change the value by
pressing the ▲ or ▼
key, and then press the
SET key to confirm the
value.

There are default
gateways from DEF1 to
DEF4. Select one using
▲ and ▼ keys and set
them one by one in the

GD-70D - 84 -

▲

SUB 1

▲

▼

SET

▼

SUB 1

SUB4)

▲

▼

SET

DEF 1

▲

▼

DEF 1

↓↑

DHCP Setting

are disabled.

● ○ ○

○

OFF

MAINTENANCE

⇔

OFF

MAINTENANCE

｜↑

▲↓↑▼

ON

PLC Mode Setting

value.

● ○ ○

○

1

⇔

5

↓↑

PLC Area Setting

value.

● ○ ○

○

0

⇔

15

↓↑

Setting Result Record

● ○ ○

○

→

↓↑

↓

MAC Address

Press the SET key to

***

▲

Select either ON/OFF,
and then press the SET
key to confirm the
selection.
When ON is selected,
an IP address is
automatically obtained
from the DHCP server.
In this case, the IP1 to
IP4, SUB1 to SUB4, and
DEF1 to DEF4 settings

Change the value by
pressing the ▲ or ▼
key, and then press the
SET key to confirm the

DHCP

▲｜｜▼

↓｜

PLC MODE

MAINTENANCE

▲

▼

▼

SET

DHCP

DHCP

MAINTENANCE

SET

PLC MODE

MAINTENANCE

Change the value by
pressing the ▲ or ▼
key, and then press the
SET key to confirm the

To record the results of
the settings made in the
above, press the SET
key.

* In ETHERNET mode, it is necessary to record setting results after all the settings have been selected.
Press the MODE key before completion to undo all the changes that have been made.

NOTE

It takes 10 seconds or more for the address settings to be recorded and for the settings to take effect on
the system. (Particularly for DHCP, the time it takes depends on the environment.) While the settings are
putting into effect, "0" is displayed for all of MAC1 - 6, IP1 - 4, SUB1 - 4 and DEF1 - 4, and none of the
Ethernet functions is av ai lable.

PLC AREA

MAINTENANCE

▲

MAINTENANCE

▲

Check
***

▼

SAVE

▼

SET

SET

PLC AREA

MAINTENANCE

SPAN Y/N

MAINTENANCE

record the setting
results and return to
SET 18. ETHERNET

- 85 - GD-70D

Task

Description

Daily

Monthly

Biannually

Power supply
check

Verify that the power lamp lights up.

○ ○ ○

Concentration

Verify that the gas reading is zero (or

adjustment.

○ ○ ○

Flow rate
check

See the flow rate indicator to check for
abnormalities.

○ ○ ○

Filter check

Check the dust filter for dust or clogging.

○ ○ ○

Alarm test

Inspect the alarm circuit by using the
alarm test function.

○

○

Span

Perform a span adjustment using

○

Gas alarm
check

Check alarm operation using calibration
gas.

○

Detection Gas

Range

Calibration Instructions

10

Maintenance

This is a critical instrument for incident prevention and saf et y.
To maintain the performance of the detector and improve its reliability, perform regular maintenance.

NOTE

To use the pyrolyzer unit (PLU-70), also refer to the individual operating manual.

10-1 Maintenance intervals and items

• Daily maintenance: perform maintenance before beginning to work.

• Monthly maintenan ce: perform mai ntenan ce on the ala rm circui t (alar m test) once a month.

• Regular maintenance: perform maintenance once every six months.

display check

adjustment

20.9 vol% for oxygen). If the reading is
not zero (or 20.9 vol%), perform a zero

calibration gas.

10-2 Calibration Overview

Calibration instructions depend on the GD-70D you are calibrating. The table below will tell you what
calibration instructions to us e based on your GD-70D’s detection gas and range.

AsH3 (Arsine) 0 - 0.20 ppm Calibrating with a Surrogate Gas (Sensors with Factors) on

page 93

B2H6 (Diborane) 0 - 0.30 ppm Calibrating with a Surrogate Gas (Sensors with Factors) on

page 93

BCl3 (Boron trichloride) 0 - 15.0 ppm Calibrating with a Gas Bag (Calibrating with HCl) on page 99

GD-70D - 86 -

Detection Gas

Range

Calibration Instructions

C2H4 (Ethylene)

0 - 2,000 ppm

Calibrating with a Humidifier (MOS Sensors) on page 103

Br2 (Bromine) 0 - 1.00 ppm Calibrating with a Surrogate Gas (Sensors with Factors) on

page 93
BTBAS (Bis[tertiary-butyl­amino]silane)
C2H2 (Acetylene) 0 - 2,000 ppm Calibrating with a Humidifier (MOS Sensors) on page 103
C2H2Cl2 (Dichloroethene) 0 - 600 ppm Calibrating with a Humidifier (MOS Sensors) on page 103

C2H5OH (Ethanol) 0 - 2,000 ppm Calibrating with a Humidifier (MOS Sensors) on page 103
C3H6 (Propylene) 0 - 5,000 ppm Calibrating with a Humidifier (MOS Sensors) on page 103
C3H8 (Propane) 0 - 2,000 ppm Calibrating with a Humidifier (MOS Sensors) on page 103

C4F6 (Hexafluorabutadiene) 0 - 200 ppm Calibrating with a Humidifier (MOS Sensors) on page 103
C4H10 (Isobutane) 0 - 100 %LEL Calibrating with a Demand Flow Regulator on page 90
C6H14 (Hexane) 0 - 2,000 ppm Cal ibrat ing with on page 90
CH2Cl2 (Dichloromethane) 0 - 2,000 ppm Calibrating with a Humidifier (MOS Sensors) on page 103
CH3CN (Acetonitrile) 0 - 2,000 ppm Calibrating with a Humidifier (MOS Sensors) on page 103
CH3COOH (Acetic acid) 0 - 30.0 ppm Calibrating with a Surrogate Gas (Sensors with Factors) on

0 - 15.0 ppm Calibrating with a Surrogate Gas (Sensors with Factors) on

page 93

0 - 5,000 ppm
0 - 100% LEL Calibrating with on page 90

page 93
CH3NH2 (Methylamine) 0 - 15.0 ppm Calibrating with a Surrogat e Gas (Sensors with Factors) on

page 93
CH3OH (Methanol) 0 - 1,000 ppm Calibrating with a Humidifier (MOS Sensors) on page 103

0 - 2,000 ppm

CH4 (Methane) 0 - 100 %LEL Calibrating with a Dem and F lo w Regulat or on pa ge 90

0 - 2% vol Calibrating with a Humidifier (MOS Sensors) on page 103
0 - 2000 ppm
0 - 5000 ppm

CH6Si (Methyl silane) 0 - 20.0 ppm Calibrating with a Surrogate Gas (Sensors with Factors) on

page 93
Cl2 (Chlorine) 0 - 3.00 ppm C alibr at ing with a Dem and F low Regu lat or on pa ge 90
ClF3 (Chlorine trifluoride) 0 - 0.60 ppm Calibrating with a Surrogate Gas (Sensors with Factors) on

page 93
CO (Carbon monoxide) 0 - 75.0 ppm Cal ibr at ing with a Dem and F low Regulator on page 90

0 - 150 ppm
0 - 300 ppm

COS (Carbonyl sulfide) 0 - 2,000 ppm Calibrating with a Humidifier (MOS Sensors) on page 103

0 - 90.0 ppm Calibrating a Pyrolyzer Unit on page 107

- 87 - GD-70D

Detection Gas

Range

Calibration Instructions

COF2 (Cobalt difluorine) 0 - 6.00 ppm Calibrating with a Surrogate Gas (Sensors with Factors) on

page 93
DEA (Diethylamine) 0 - 15.0 ppm Calibrating with a Surrogate Gas (Sensors with Factors) on

page 93
DMA (Dimethylamine) 0 - 15.0 ppm Calibrating with a Surrogate Gas (Sensors with Factors) on

page 93
F2 (Fluorine) 0 - 1.00 ppm Calibrating with a Surrogate Gas (Sensors with Factors) on

0 - 3.00 ppm

page 93
GeH4 (Germane) 0 - 0.80 ppm Calibrating with a Surrogate Gas (Sensors with Factors) on

page 93
H2 (Hydrogen)

0 - 100 %LEL Calibrating with a Dem and Flo w Regu lat or on page 90
0 - 2.00 %volume Calibrating with a Humidifier (MOS Sensors) on page 103
0 - 500 ppm
0 - 1,000 ppm
0 - 2,000 ppm

0 - 4,000 ppm
H2Cl2Si (Dichlorosilane) 0 - 15.0 ppm Calibrating with a Gas Bag (Calibrating with HCl) on page 99
H2O2 (Hydrogen peroxide) 0 - 3.00 ppm Calibrating with a Surrogate Gas (Sensors with Factors) on

page 93

H2S (Hydrogen sulfide) 0 - 1.00 ppm Calibrating with a Demand Flow Regulator on page 90

0 - 30.0 ppm
H2Se (Hydrogen selenide) 0 - 0.20 ppm Calibrating with a Surrogate Gas (Sensors with Factors) on

page 93

H9NSi3 (Trisilylamine) 0 - 15.0 ppm Calibrating with a Surrogate Gas (Sensors with Factors) on

page 93

HBR (Hydrogen bromide) 0 - 6.00 ppm Calibrating with a Gas Bag (Calibrating with HCl) on pa ge 99

0 - 9.00 ppm
HCl (Hydrogen chloride) 0 - 6.00 ppm Calibrating with a Gas Bag (Calibrating with HCl) on page 99

0 - 15.0 ppm
HCN (Hydrogen cyanide) 0.9 - 15.0 ppm C alibr at ing with a Dem and F lo w Regulat or on pa ge 90
HCOOH (Formic acid) 0 - 15.0 ppm Calibrating with a Surrogate Gas (Sensors with Factors) on

page 93

HF (Hydrogen fluoride) 0.4 - 3.00 ppm Calibrat ing with a Surro gate Gas (Sensors with Factors) on

0.4 - 9.00 ppm

page 93

HNO3 (Nitric acid) 0 - 20.0 ppm Calibrating with a Surrogate Gas (Sensors with Factors) on

page 93

GD-70D - 88 -

Detection Gas

Range

Calibration Instructions

IPA (Isopropyl alcohol) 0 - 2,000 ppm Calibrating with a Humidifier (MOS Sensors) on page 103

0 - 100 %LEL Calibrating with a Surrogate Gas (Sensors with Factors) on

page 93
N2O (Nitrous oxide) 0 - 500 ppm Calibrating with a Demand Flow Regulator on page 90
N2H4 (Hydrazine) 0 - 5.00 ppm Calibrating with a Surrogate Gas (Sensors with Factors) on

page 93
NF3 (Nitrogen trifluoride) 0 - 30.0 ppm Calibrating a Pyrolyzer Unit on page 107
NH3 (Ammonia) 0 - 75.0 ppm Calibrat ing with a Demand Flow Regulator on pa ge 90
NO (Nitric oxide) 0 - 100 ppm Cal ibrating with a Demand Flow Regulat or on pa ge 90
NO2 (Nitrogen dioxide) 0 - 9.00 ppm Calibr at ing with a Dem and F low Regu lat or on pa ge 90

0 - 15.0 ppm

O2 (Oxygen) 0 - 5.00% Calibr at ing with a Dem and F lo w Regulat or on pa ge 90

0 - 25.0% Cal ibrat ing with a Demand Flow Regulator on page 90

O3 (Ozone) 0 - 0.60 ppm Calibrating with a Surrogate Gas (Sensors with Factors) on

0 - 1.00 ppm
PH3 (Phosphine) 0 - 1.00 ppm Calibrat ing with a Demand Flow Regulator on page 90
R32 (Difluoromethane) 0 - 2,000 ppm Calibrating with a Humidifier (MOS Sensors) on page 103

0 - 5,000 ppm

0 - 9,000 ppm
R41 (Fluoromethane) 0 - 2,000 ppm Calibrating with a Humidifier (MOS Sensors) on page 103
TEOS (Tetraethyl orthosilicate) 0 - 15.0 ppm Calibrating a Pyrolyzer Unit on page 107
TMA (Trimethylamine) 0 - 15.0 ppm Calibrating with a Surrogate Gas (Sensors with Factors) on

TMB (Trimethoxy borane) 0 - 1000 ppm Calibrating a Pyrolyzer Unit on page 107
TMS (Tetramethyl silane) 0 - 15.0 ppm Calibrating a Pyrolyzer Unit on page 107
TRIMS (Trimethyl silane) 0 - 15.0 ppm Calibrating a Pyrolyzer Unit on page 107
Si2H6 (Disilane) 0 - 15.0 ppm Calibrating with a Surrogate Gas (Sensors with Factors) on

SiCl4 (Silicon tetrachloride) 0 - 15.0 ppm Calibrating with a Gas Bag (Calibrating with HCl) on page 99
SiH4 (Silane) 0 - 15.0 ppm Cal ibrating with a Demand Flow Regulator on pa ge 90

page 93

page 93

page 93

SO2 (Sulphur dioxide) 0 - 6.00 ppm Calibrating with a Dem and F lo w Regulat or on pa ge 90

- 89 - GD-70D

Detection Gas

Range

Calibration Gas/Concentration

Warm Up Time
After Power-Up

10-3 Calibrating with the Target Gas

The calibration instructions in this section apply ONLY to the sensors listed in the table below. If your
sensor is not listed in the table below, you will need to follo w the instructions outlined in one of the other
calibration sections. The warm up times listed are the minimum times between powering up a GD-70D and
calibrating that GD-70D.

C3H8 (Propane) 0 - 100 %LEL Propa ne: 50% LE L 2 hours
C4H10 (Isobutane) 0 - 100 %LEL Is obuta ne: 50% LEL 2 hours
C6H14 (Hexane) 0 - 100 %LEL Hexane: 50% LEL 2 hours
CH4 (Methane) 0 - 100 %LEL Methane: 50% LEL 2 hours
Cl2 (Chlorine) 0 - 3.00 ppm Chlorine: 2 ppm 3 hours
CO (Carbon monoxide) 0 - 75.0 ppm Carbon monoxide: 50 ppm 3 hours

0 - 150 ppm Carbon monoxide: 100 pp m 3 hours

0 - 300 ppm Carbon monoxide: 200 pp m 3 hours
H2 (Hydrogen)
H2S (Hydrogen sulfide) 0 - 1.00 ppm Hydrogen sulfide (H2S): 1 ppm 3 hours

HCN (Hydrogen cyanide) 0.9 - 15.0 ppm Hydrogen cyanide (HCN): 10 ppm 3 hours
N2O (Nitrous oxide) 0 - 500 ppm Nitrous oxide (NO): 250 ppm 1 hour
NH3 (Ammonia) 0 - 75.0 ppm Ammonia (NH3): 50 ppm 3 hours
NO (Nitric oxide) 0 - 100 ppm Nitric oxide (NO): 25 ppm 3 hours
NO2 (Nitrogen dioxide) 0 - 9.00 ppm Nitrog en diox ide (NO2): 5 ppm 6 hours

O2 (Oxygen) 0 - 5.00% Oxygen (O2): 2% for span

PH3 (Phosphine) 0 - 1.00 ppm Phosphine (PH3): 0.5 ppm 6 hours
SiH4 (Silane) 0 - 15.0 ppm Silane (SiH4): 5 ppm 6 hours
SO2 (Sulphur dioxide) 0 - 6.00 ppm Sulphur dioxide (SO2): 5 ppm 3 hours

0 - 100 %LEL Hydrogen (H2): 50% LEL 2 hours

0 - 30.0 ppm Hydrogen sulfide (H2S): 15 ppm 3 hours

0 - 15.0 ppm Nitr og en diox ide (NO2): 10 ppm 6 hours

10 minutes

Nitrogen (N2): 100% for zero

0 - 25.0% Fresh air for span

Nitrogen (N2): 100% for zero

3 hours

Calibration Equipment

• Demand flow regulator (RKI Instruments, Inc. recommends that you dedicate one regulator each
for Cl2 and H2S and that you not use that regulator for any other gas)

• Calibration tubing

• Calibration cylinder of appropriate concentration

Preparing for Calibration

GAS IN Fitting
Remove the dust filter and the sample line from the GAS IN fitting’s tubing stub.

Regulator
Screw the demand flow regulator onto the calibration cylinder.

GD-70D - 90 -

Accessing Maintenance Mode

0.0ppm

↓

↓

1- 8

MAINTENANCE

↓

↓

User Mode

1- 8

MAINTENANCE

↓

↓

Then press and hold the SET key again for three seconds.

- - - -

MAINTENANCE

↓

↓

2-0.GAS TEST

2- 0

MAINTENANCE

2-1. ZERO

Press the SET key.

2- 1

↓

Current Concentration Value Display

1.1ppm

MAINTENANCE

↓

Zero Adjustment Completed

0.0ppm

MAINTENANCE

0.0ppm

MAINTENANCE

↓

↓

Return to 2-1.ZERO

Return to 2-1.ZERO

From Detection Mode, press and hold the MODE key for three seconds.

1-8.M MODE
Press the ▲ key until the Maintenance Mode screen displays. (For GD-

70D-EA units, the Maintenance Mode screen is item 1-9.)

In "1-8.M MODE", press the SET key.

SIH4

M MODE

M MODE

The first item in Maintenance Mode will display.

Performing a Zero Adjustment

Press the ▲ key until the ZERO screen
displays.

Press the SET key to perform the zero
adjustment.

M MODE

GAS TEST

ZERO

MAINTENANCE

ZERO SET

The instrument will indicate whether the zero
adjustment passed (OK) or failed (NG) and
will return to 2-1.ZERO automatically.

- 91 - GD-70D

ZERO OK

OR

ZERO NG

Do not press the SET key befor e the readi ng is stabil iz ed.

2-2. SPAN

Press the SET key.

2- 2

Allow gas to flow for 2 minutes.

↓

↓

Accept Reading

scale value in order to continue.

2.0ppm

Disconnect Gas

tubing stub on the GAS IN fitting.

↓

↓

Span Adjustment

Press the SET key.

8.0ppm

MAINTENANCE

↓

↓

Span Adjustment Completed

8.0ppm

MAINTENANCE

8.0ppm

MAINTENANCE

↓

↓

↓

Return to 2-2.SPAN

Save Adjustment

8.0ppm

MAINTENANCE

↓

↓

Adjustment Completed

8.0ppm

MAINTENANCE

Performing a Span Adjustment

Press the ▲ key until the SPAN screen
displays.

Connect Gas
Use the calibration tubing to connect the
demand flow regulator to the tubing stub on
the GAS IN fitting. Gas will begin to flow.

Press the SET key when the reading has
stabilized.
* The reading must be above 10% of the full

CAUTION

SPAN

MAINTENANCE

SPAN GAS

MAINTENANCE

Disconnect the calibration tubing from the

Using the ▲ or ▼ keys, adjust the reading to
match the concentration listed on your
calibration cylinder.

The instrument will indicate whether the span
adjustment passed (OK) or failed (NG).

To save the adjustment result, press the SET
key.
(Press the MODE key to cancel this menu.)

SPAN VAL

SPAN OK

SPAN Y/N

OR

SPAN NG

After the span has been recorded, the
instrument will return to 2-2.SPAN
automatically.

GD-70D - 92 -

SPAN END

↓

Return to 2-2.SPAN

Detection Gas

Range

Calibration Gas/Concentration

Warm Up Time
After Power-Up

through the exhaust line.

CAUTION

Exhaust gas must be collected
in the exhaust bag or discharged

Returning to Detection Mode

Store the components of the calibration kit in a safe place.
Reconnect the dust filter and inlet line to the GAS IN fitting.
Press and hold the MODE key to return to Detection Mode.

10-4 Calibrating with a Surrogate Gas (Sensors with Factors)

The calibration instructions in this section apply ONLY to the sensors listed in the table below. If your
sensor is not listed in the table below, you will need to follow the instructions outlined in one of the other
calibration sections. The warm up times listed are the minimum times between powering up a GD-70D and
calibrating that GD-70D.

AsH3 (Arsine) 0 - 0.20 ppm Phosphine (PH3): 0.5 ppm** 24 hours
B2H6 (Diborane) 0 - 0.30 ppm Phosphine (PH3): 0.5 ppm** 24 hours

Br2 (Bromine) 0 - 1.00 ppm Chlorine (Cl2): 2 ppm** 3 hours
BTBAS (Bis[tertiary-butyl­amino]silane)
CH3COOH (Acetic acid) 0 - 30.0 ppm Chlorine (Cl2): 2 ppm** 3 hours
CH3NH2 (Methylamine) 0 - 15.0 ppm Ammonia (NH3): 5 ppm** 6 hours
CH6Si (Methylsilane) 0 - 20.0 ppm Silane (SiH4): 5 ppm* 3 hours
ClF3 (Chlorine trifluoride) 0 - 0.60 ppm Chlorine (Cl2): 2 ppm* 3 hours
COF2 (Cobalt difluorine) 0 - 6.00 ppm Chlorine (Cl2): 2 ppm** 3 hours
DEA (Diethylamine) 0 - 15.0 ppm Ammonia (NH3): 5 ppm** 24 hours
DMA (Dimethylamine) 0 - 15.0 ppm Ammonia (NH3): 5 ppm** 6 hours
F2 (Fluorine) 0 - 3.00 ppm Chlorine (Cl2): 2 ppm or 5 ppm*** 3 hours

GeH4 (Germane) 0 - 0.80 ppm Silane (SiH4): 5 ppm** 3 hours
H2O2 (Hydrogen peroxide) 0 - 3.00 ppm Phosphine (PH3): 0.5 ppm * 3 hours

0 - 15.0 ppm Ammonia (NH3): 5 ppm* 6 hours

0 - 1.00 ppm Chlorine (Cl2): 2 ppm** 3 hours

H2Se (Hydrogen selenide) 0 - 0.20 ppm Phosphine (PH3): 0.5 ppm** 24 hours
H9NSi3 (Trisilylamine) 0 - 15.0 ppm Silane (SiH4): 30 ppm* 3 hours
HCOOH (Formic acid) 0 - 15.0 ppm Chlorine (Cl2): 2 ppm* 3 hours
HF (Hydrogen fluoride) 0.4 - 9.00 ppm Chlorine (Cl2): 2 ppm or 5 ppm*** 3 hours
HNO3 (Nitric acid) 0 - 20.0 ppm Chlorine (Cl2): 2 ppm or 5 ppm*** 3 hours

- 93 - GD-70D

Detection Gas

Range

Calibration Gas/Concentration

Warm Up Time
After Power-Up

* No dilution needed.

factor should be as close to 50% of full scale as possible.

IPA (Isopropyl alcohol) 0 - 100 %LEL Isobutane (C4H10): 50% LEL*

N2H4 (Hydrazine) 0 - 5.00 ppm Nitrous oxide (NO): 10 ppm* 6 hours
O3 (Ozone) 0 - 0.60 ppm Chlorine (Cl2): 2 ppm** 3 hours

Si2H6 (Disilane) 0 - 15.0 ppm Silane (SiH4): 5 ppm or 30 ppm*** 3 hours
TMA (Trimethylamine) 0 - 15.0 ppm Ammonia (NH3): 5 ppm** 6 hours

** Gas may or may not need dilution depending on the sensor’s factor. The calibration gas multiplied
by the factor should be as close to 50% of full scale as possible.
*** Use one of the two gases listed, depending on sensor’s factor. The calibration gas multiplied by the

Discussion for **

Gases with a ** next to them in the table above may or may not need to be diluted before being used to
calibrate the GD-70D. In order to figure out if you need to dilute the gas, multiply the gas concentration
listed on your calibration cylinder by the factor listed on the sensor unit at the GD-70D. The result should
be something between 10% and 100% of full scale for the sensor. A value closest to 50% of full scale is
ideal but if you can get somewhere between 10% and 100% of full scale without diluting, that is also fine.

Discussion for ***

For gases with a *** next to them in the table above, different concentrations of calibration gas need to be
used depending on the factor listed on the sensor unit. The goal is to have the calibration gas multiplied by
the factor be as close to 50% of full scale as possible. It is not necessary to dilute these gases to achieve
that goal. The concentration listed on the calibration cylinder multiplied by the factor listed on the sensor
should be as close to 50% of full scale as possible but any value between 10% and 100% of full scale can
be used to calibrate.

Calibration Equipment for Gases Needing Dilution

• 0.5 LPM fixed flow regulator (RKI Instruments, Inc. recommends that you dedicate one regulator
each for Cl2 and that you not use that regulator for any other gas)

• Tedlar gas collection bag with hose and hose clam p

• Calibration cylinder

• 100% nitrogen (N2) cylinder

• Stopwatch or other timing device

Calibration Equipment for Gases Not Needing Dilution

• Demand flow regulator

• Calibration tubing

• Calibration cylinder of appropriate concentration

Preparing for Calibration – Gases Needing Dilution

Determining Needed Calibration Gas Concentration
Before performing a calibration, you must mix your calibration gas in a gas bag. You need to first
determine what final concentration of calibration gas you need.

     (1      2)

The final concentration multiplied by the sensor’s factor must be between 10% and 100% of full scale.
Ideally, the final concentration multiplied by the sensor’s factor should be as close to 50% of full scale as
possible, but something different is acceptable as long as it’s higher than 10% of full scale and less than
100% of full scale. For example, a gas bag full of 0.1 ppm PH3 multiplied by a factor of 1.7 is 0.17 ppm
which is below the full scale value of 0.20 ppm for AsH3 or H2Se.

GD-70D - 94 -

0 - 1.00 ppm Chlorine (Cl2): 2 ppm** 3 hours

   

2 hours

(SET GD-70D TO 60% LEL)

×   <   

Total Parts in Gas Bag

(from discussion in previous section)

Gas Flow Time

Nitrogen Flow Time

2 (1 part gas, 1 part N2)

1 minute

1 minute

3 (1 part gas, 2 parts N2)

1 minute

2 minutes

4 (1 part gas, 3 parts N2)

45 seconds

2 minutes 15 seconds

5 (1 part gas, 4 parts N2)

30 seconds

2 minutes

6 (1 part gas, 5 parts N2)

20 seconds

1 minute 40 seconds

7 (1 part gas, 6 parts N2)

20 seconds

2 minutes

8 (1 part gas, 7 parts N2)

15 seconds

1 minute 45 seconds

9 (1 part gas, 8 parts N2)

15 seconds

2 minutes

10 (1 part gas, 9 parts N2)

12 seconds

1 minute 48 seconds

Phosphine does not come in cylinders of 0.1 ppm concentration so you need to determine how much to
dilute the cylinder that you have. For example, a cylinder of 0.5 ppm PH3 diluted 1 part gas to 4 parts
nitrogen (5 parts total) would give you 0.1 ppm PH3:

0.5  3

5

× 1.7 = 0.17   < 0.20 

But if you had a higher concentration of PH3 in your calibration cylinder or if your sensor’s factor is higher
than 1.7, you would need to increase the dilution.

1.0  3

5

× 1.7 = 0.34    < 0.20 

Changing the dilution to 1 part gas to 8 parts nitrogen (9 parts total):

1.0  3

9

× 1.7 = 0.19   < 0.20 

Determining How to Fill Gas Bag
After determining the required dilution, you will need to determine how to fill your gas bag (ie. how long to
let each cylinder flow). The GD-70D will need approximately 1 liter of gas for a 2 minute calibration. The
fixed flow regulator used to fill the gas bag flows at 0.5 LPM.

The table below provides suggestions for gas flow times based on level of dilution needed. The times listed
assume you have a 2 liter gas bag and will provide between 1 and 1.5 liters of gas which is enough to
calibrate one detector head. If you want to mix a gas once and calibrate multiple detector heads with it, you
will need a bag larger than 2 liters and you will need to increase the times listed below.

Table 1: Gas Flow Times for Gas Bag Dilution

Filling the Gas Bag

1. If not already installed, install the hose and hose clamp on the gas bag.

2. Open the hose clamp on the gas bag.

3. Be sure the gas bag is completely empty.

4. Connect the tubing on the gas bag to the fixed flow regulator’s hose barb fitting. Be sure the regulator’s
knob is in the closed position.

5. Screw the fixed flow regulator onto the calibration cylinder.

6. Turn the regulator’s knob counterclockwise. Allow the gas to flow for the appropriate amount of time
based on your dilution needs. See Table 1 above.

7. Turn the regulator’s knob clockwise to close it.

8. Clamp down on the hose clamp to prevent the release of gas from the gas bag.

9. Remove the gas bag from the regulator.

10. Unscrew the regulator from the calibration cylinder and screw it onto a 100% N2 cylinder.

11. Connect the gas bag tubing to the regulator’s hose barb fitting.

12. Open the hose clamp on the gas bag.

13. Turn the regulator’s knob counterclockwise. Allow the gas to flow for the appropriate amount of time
based on your dilution needs. See Table 1 above.

14. Turn the regulator’s knob clockwise to close it.

- 95 - GD-70D

Accessing Maintenance Mode

0.0ppm

↓

↓

1-8.M MODE

1- 8

MAINTENANCE

↓

↓

User Mode

1- 8

MAINTENANCE

↓

↓

Then press and hold the SET key again for three seconds.

- - - -

MAINTENANCE

↓

↓

2-0.GAS TEST

2- 0

MAINTENANCE

Press the SET key.

2- 1

↓

Current Concentration Value Display

1.1ppm

MAINTENANCE

↓

15. Clamp down on the hose clamp to prevent the release of gas from the gas bag.

16. Remove the gas bag from the regulator.

17. Unscrew the regulator from the 100% N2 cylinder.

18. Continue to Entering Calibration Mode below.

Preparing for Calibration – Gases Not Needing Dilution

Regulator
Screw the demand flow regulator onto the calibration cylinder.

Entering Calibration Mode

GAS IN Fitting
Remove the dust filter and the sample line from the GAS IN fitting’s tubing stub.

From Detection Mode, press and hold the MODE key for three seconds.

SIH4

Press the ▲ key until the Maintenance Mode screen displays. (For GD-

70D-EA units, the Maintenance Mode screen is item 1-9.)

M MODE

In "1-8.M MODE", press the SET key.

The first item in Maintenance Mode will display.

Performing a Zero Adjustment

2-1. ZERO
Press the ▲ key until the ZERO screen
displays.

M MODE

M MODE

GAS TEST

ZERO

MAINTENANCE

Press the SET key to perform the zero
adjustment.

GD-70D - 96 -

ZERO SET

Do not press the SET key befor e the readi ng is stabil iz ed.

Zero Adjustment Completed

0.0ppm

MAINTENANCE

0.0ppm

MAINTENANCE

↓

↓

Return to 2-1.ZERO

Return to 2-1.ZERO

2-2. SPAN

Press the SET key.

2- 2

Connect Gas

Allow gas to flow for 2 minutes.

↓

↓

Accept Reading

scale value in order to continue.

2.0ppm

Disconnect Gas

tubing stub on the GAS IN fitting.

↓

↓

The instrument will indicate whether the zero
adjustment passed (OK) or failed (NG) and
will return to 2-1.ZERO automatically.

Performing a Span Adjustment

Press the ▲ key until the SPAN screen
displays.

Open the hose clamp on the gas bag and
immediately connect the tubing to the tubing
stub on the GAS IN fitting
OR
Use the calibration tubing to connect the
demand flow regulator to the tubing stub on
the GAS IN fitting.

ZERO OK

SPAN

MAINTENANCE

OR

ZERO NG

Press the SET key when the reading has
stabilized.
* The reading must be above 10% of the full

CAUTION

Close the gas bag’s hose clamp and
immediately remove the gas bag from the
tubing stub on the GD-70D’s GAS IN fitting.
OR
Disconnect the calibration tubing from the

SPAN GAS

MAINTENANCE

- 97 - GD-70D

Span Adjustment

Press the SET key.

8.0ppm

MAINTENANCE

↓

↓

Span Adjustment Completed

8.0ppm

MAINTENANCE

8.0ppm

MAINTENANCE

↓

↓

↓

Return to 2-2.SPAN

Save Adjustment

8.0ppm

MAINTENANCE

↓

↓

Adjustment Completed

8.0ppm

MAINTENANCE

↓

Return to 2-2.SPAN

Using the ▲ or ▼ keys, adjust the reading to
match the concentration in the gas bag
multiplied by the conversion factor on the
sensor OR to the value listed in the table at
the beginning of this section.

For example, a gas bag of 0.1 ppm PH3
multiplied by a conversion factor of 1.7 is 0.17
ppm AsH3 or H2Se.

The instrument will indicate whether the span
adjustment passed (OK) or failed (NG).

SPAN VAL

SPAN OK

OR

SPAN NG

To save the adjustment result, press the SET
key.
(Press the MODE key to cancel this menu.)

After the span has been recorded, the
instrument will return to 2-2.SPAN
automatically.

Returning to Detection Mode

Store the components of the calibration kit in a safe place.
Reconnect the dust filter and inlet line to the GAS IN fitting.
Press and hold the MODE key to return to Detection Mode.

CAUTION

Exhaust gas must be collected
in the exhaust bag or discharged
through the exhaust line.

SPAN Y/N

SPAN END

GD-70D - 98 -

Detection Gas

Range

Calibration Gas/Concentration

Warm Up Time
After Power-Up

* May or may not need dilution. In order to figure out if you need to dilute the gas, multiply the gas

diluting, that is also fine.

10-5 Calibrating with a Gas Bag (Calibrating with HCl)

The calibration instructions in this section apply ONLY to the sensors listed in the table below. If your
sensor is not listed in the table below, you will need to follow the instructions outlined in one of the other
calibration sections. The warm up times listed are the minimum times between powering up a GD-70D and
calibrating that GD-70D.

BCl3 (Boron trichloride) 0 - 15.0 ppm Hydrogen chloride (HCl): 5 ppm 6 hours
H2Cl2Si (Dichlorosilane) 0 - 15.0 ppm Hydrogen chloride (HCl): 5 ppm 6 hours
HBr (Hydrogen bromide) 0 - 6.00 ppm Hydrogen chloride (HCl): 5 ppm* 24 hours

0 - 9.00 ppm Hydrogen chloride (HCl): 5 ppm * 24 hours

HCl (Hydrogen chloride) 0 - 6.00 ppm Hydrogen chloride (HCl): 5 ppm 6 hours

0 - 15.0 ppm Hydrogen chloride (HCl): 5 ppm 6 hours

SiCl4 (Silicon tetrachloride) 0 - 15.0 ppm Hydrogen chloride (HCl): 5 ppm 6 hours

concentration listed on your calibration cylinder by the factor listed on the sensor unit at the GD-70D.
The result should be something between 10% and 100% of full scale for the sensor. A value closest to
50% of full scale is ideal but if you can get somewhere between 10% and 100% of full scale without

Calibration Equipment – No Dilution Needed

• 6 LPM fixed flow regulator (RKI Instruments, Inc. recommends that you dedicate one regulator for

use with HCl and that you not use that regulator for any other gas)

• Gas bag with tubing and a hose clamp

• Calibration cylinder of appropriate concentration

Calibration Equipment – 1:1 Dilution Needed

• 6 LPM fixed flow regulator (RKI Instruments, Inc. recommends that you dedicate one regulator for:

use with HCl and that you not use that regulator for any other gas)

• Gas bag with tubing and a hose clamp

• Calibration cylinder of appropriate concentration

• 100% N2 cylinder

Preparing for Calibration – No Dilution Needed

Filling the Gas Bag
RKI Instruments, Inc. recommends screwing a nitrogen calibration cylinder onto the fixed flow regulator
and purging the regulator for 30 seconds before starting the calibration process.

1. If not already installed, install the hose and hose clamp on the gas bag.

2. Open the hose clamp on the gas bag.

3. Be sure the gas bag is completely empty.

4. Connect the tubing on the gas bag to the fixed flow regulator’s hose barb fitting. Be sure the regulator’s
knob is in the closed position.

5. Screw the fixed flow regulator onto the calibration cylinder.

6. Turn the regulator’s knob counterclockwise.

7. Allow the gas to flow until the gas bag is about half full.

8. Turn the regulator’s knob clockwise to close it.

9. Close the hose clamp.

10. Disconnect the gas bag from the regulator.

11. Unscrew the regulator from the calibration cylinder.

12. Continue to Entering Calibration Mode below.

- 99 - GD-70D

GAS IN Fitting

Accessing Maintenance Mode

0.0ppm

↓

↓

1- 8

MAINTENANCE

↓

↓

User Mode

1- 8

MAINTENANCE

↓

↓

Then press and hold the SET key again for three seconds.

- - - -

MAINTENANCE

↓

↓

Preparing for Calibration – 1:1 Dil uti on Needed

Filling the Gas Bag
RKI Instruments, Inc. recommends screwing a nitrogen calibration cylinder onto the fixed flow regulator
and purging the regulator for 30 seconds before starting the calibration process.

1. If not already installed, install the hose and hose clamp on the gas bag.

2. Open the hose clamp on the gas bag.

3. Be sure the gas bag is completely empty.

4. Connect the tubing on the gas bag to the 6LPM fixed flow regulator’s hose barb fitting. Be sure the
regulator’s knob is in the closed position.

5. Screw the fixed flow regulator onto the calibration cylinder.

6. Turn the regulator’s knob counterclockwise. Allow the gas to flow for 7 seconds.

7. Turn the regulator’s knob clockwise to close it.

8. Clamp down on the hose clamp to prevent the release of gas from the gas bag.

9. Remove the gas bag from the regulator.

10. Unscrew the regulator from the calibration cylinder and screw it onto a 100% N2 cylinder.

11. Connect the gas bag tubing to the regulator’s hose barb fitting.

12. Open the hose clamp on the gas bag.

13. Turn the regulator’s knob counterclockwise. Allow the gas to flow for 7 seconds.

14. Turn the regulator’s knob clockwise to close it.

15. Clamp down on the hose clamp to prevent the release of gas from the gas bag.

16. Remove the gas bag from the regulator.

17. Unscrew the regulator from the 100% N2 cylinder.

18. The gas concentration in the gas bag is half of what is listed on the HCl calibration cylinder.

19. Continue to Entering Calibration Mode below.

Entering Calibration Mode

Remove the dust filter and the sample line from the GAS IN fitting’s tubing
stub.

From Detection Mode, press and hold the MODE key for three seconds.

(For GD-70D-EA units, the Maintenance Mode screen is item 1-9.)

1-8.M MODE
Press the ▲ key until the Maintenance Mode screen displays.

In "1-8.M MODE", press the SET key.

SIH4

M MODE

M MODE

GD-70D - 100 -

M MODE