Detcon TP-524D User Manual

INSTRUCTION MANUAL

Detcon Model TP-524D

PGM 1

MODEL TP-524DHOUSTON,TEXAS

TM

MicroSafe H2S Gas Sensor

ALM ALM

FLT 1 2 CAL

PGM 2

TP-524D Hydrogen Sulfide Sensor

This manual covers the following ranges:

0-20ppm, 0-50ppm, and 0-100ppm

DETCON, Inc.

4055 Technology Forest Blvd, Suite 100,

The Woodlands, Texas 77381

Ph.281.367.4100 / Fax [phone]

www.detcon.com

March 10, 2014 • Document #3269 • Revision 0.5

This page left intentionally blank

Model TP-524D

Model TP-524D ii

Model TP-524D

Table of Contents

1. Introduction ..................................................................................................................................................1

1.1 Description.......................................................................................................................................... 1

1.2 Modular Mechanical Design............................................................................................................... 2

2. Installation....................................................................................................................................................4

2.1 ATEX Operational Guidelines for Safe Use....................................................................................... 4

2.2 Sensor Placement................................................................................................................................ 4

2.3 Sensor Contaminants and Interference ............................................................................................... 5

2.4 Mounting Installation.......................................................................................................................... 6

2.5 Electrical Installation.......................................................................................................................... 7

2.6 Field Wiring........................................................................................................................................ 8

2.7 Initial Start Up..................................................................................................................................... 9

3. Operation....................................................................................................................................................11

3.1 Programming Magnet Operating Instructions................................................................................... 11

3.2 Operator Interface............................................................................................................................. 12

3.3 Normal Operation ............................................................................................................................. 14

3.4 Calibration Mode (AutoSpan)........................................................................................................... 14

3.5 Program Mode .................................................................................................................................. 16

3.5.1 View Sensor Status....................................................................................................................... 16

3.5.2 Set AutoSpan Level...................................................................................................................... 18

3.5.3 Set Range...................................................................................................................................... 18

3.5.4 Set Heater Power.......................................................................................................................... 19

3.5.5 Signal Output Check..................................................................................................................... 20

3.5.6 Restore Factory Defaults.............................................................................................................. 20

3.5.7 Alarm 1 and 2 Settings ................................................................................................................. 21

3.5.8 Fault Settings................................................................................................................................ 21

3.6 Program Features.............................................................................................................................. 22

3.6.1 Operational Features..................................................................................................................... 22

3.6.2 Fault Diagnostic/Failsafe Features ............................................................................................... 22

4. Service and Maintenance............................................................................................................................25

5. Troubleshooting Guide...............................................................................................................................27

6. Customer Support and Service Policy........................................................................................................30

7. TP-524D Sensor Warranty .........................................................................................................................31

8. Appendix ....................................................................................................................................................32

8.1 Specifications.................................................................................................................................... 32

8.2 Spare Parts, Sensor Accessories, Calibration Equipment................................................................. 34

8.3 Revision Log..................................................................................................................................... 35

Model TP-524D iii

Model TP-524D

Table of Figures

Figure 1 Sensor Assembly Front View ................................................................................................................ 1

Figure 2 Circuit Functional Block Diagram......................................................................................................... 2

Figure 3 Transmitter Module ............................................................................................................................... 2

Figure 4 Field Replaceable H2S Sensor................................................................................................................ 3

Figure 5 Base Connector Board ........................................................................................................................... 3

Figure 6 TP 524D ATEX Approval Labels.......................................................................................................... 4

Figure 7 Typical Outline and Mounting Dimensions........................................................................................... 7

Figure 8 Typical Installation ................................................................................................................................ 8

Figure 9 Sensor Connector PCB........................................................................................................................... 9

Figure 10 Magnetic Programming Tool............................................................................................................. 11

Figure 11 Magnetic Programming Switches...................................................................................................... 11

Figure 12 TP-524D Software Flowchart............................................................................................................ 13

Figure 13 Replaceable H2S Sensor..................................................................................................................... 27

List of Tables

Table 1 Cross Interference Gases......................................................................................................................... 6

Table 2 Wire Gauge vs. Distance......................................................................................................................... 8

Shipping Address: 4055 TechnologyForest Blvd, Suite 100, The Woodlands Texas 77381

Phone: [phone] • Fax: [phone] • www.detcon.com • [e-mail]

Model TP-524D iv

Mailing Address: P.O. Box 8067, The Woodlands Texas 77387-8067

Model TP-524D

1. Introduction

1.1 Description

Detcon Model TP-524D hydrogen sulfide sensors are non-intrusive “Smart” sensors designed to detect and
monitor H2S in air. Ranges of detection are 0-20ppm, 0-50ppm, and 0-100ppm. The sensor features an LED
display of current reading, fault, and calibration status. The Sensor is equipped with a standard analog 4­20mA output. A primary feature of the sensor is its method of automatic calibration, which guides the user
through each step via fully scripted instructions displayed on the LED display.

The microprocessor-supervised electronics are packaged as a plug-in replaceable Transmitter Module that is
housed in an explosion proof junction box. The Transmitter Module includes a four character alpha/numeric
LED used to display sensor readings, and the sensor’s menu driven features when the hand-held programming
magnet is used.

PGM 1

MODEL TP-524DHOUSTON,TEXAS

TM

MicroSafe H2S Gas Sensor

ALM ALM

FLT 1 2 CAL

PGM 2

Figure 1 Sensor Assembly Front View

Solid State H2S Sensor Technology

The sensor technology is a patented solid-state mixed metal oxide semiconductor.
The sensor consists of two thin films, a temperature sensitive heater film, and a
hydrogen sulfide sensitive sensor film. Both films are deposited on a silicon
microchip by vacuum deposition. The heater film elevates the operating
temperature of the sensor film to a level where a good sensitivity and response to
hydrogen sulfide is achieved. The sensor film is a proprietary mixed metal oxide
that shows an extremely stable and dynamic response to hydrogen sulfide gas.

Range of sensitivity is from parts per billion to percent by volume. The rugged
sensor is capable of maintaining its operating characteristics for periods of up to 7­10 years in most industrial environments and as such, is supported by a 10-year
conditional warranty.

TP-524D Instruction Manual Rev. 0.5 Page 1 of 36

Model TP-524D

RS-4854-

20mA

Display

Control

Pre-Amp

Power Supply

Principle of Operation

Method of detection is by diffusion/adsorption. Air and H2S diffuse through a sintered stainless steel filter
(flame arrestor) and contact the heated surface of the metal oxide sensor film. As hydrogen sulfide gas
molecules react with oxygen ions on the film, there is a decrease in electrical resistance proportional to the gas
concentration. The heater film elevates the temperature of the sensor film creating convection and promoting
a quick response to changing gas concentrations. Electronically, the heater film is used to maintain a constant
temperature of the sensor film enhancing stability and repeatability. The sensor response is reversible and
results in continuous monitoring of ambient air conditions.

1.2 Modular Mechanical Design

The Model TP-524D Sensor Assembly is completely modular and is made up of four parts:

1) TP-524D Plug-in Transmitter

2) Field Replaceable H2S Gas Sensor

3) Connector PCB

4) Splash Guard.

TP-524D Plug-in Transmitter

The Plug-in Transmitter Module is a microprocessor-based package that plugs into the connector board located
in the explosion proof junction box. Circuit functions include extensive I/O circuit protection, sensor pre­amplifier, sensor temperature control, on-board power supplies, microprocessor, LED display, magnetic
programming switches, and a linear 4-20mA DC output. Magnetic program switches located on either side of
the LED Display are activated via a hand-held magnetic programming tool, thus allowing non-intrusive
operator interface with the Transmitter Module. Calibration can be accomplished without declassifying the
area. Electrical classifications are Class I, Division 1, Groups B C D.

Plug-In

Sensor

Element

Temperature

Micro-

Processor

I/O

Circuit

Protection

Analog 4-20mA Out

Power In

Figure 2 Circuit Functional Block Diagram

PGM 1

HOUSTON,TEXAS

TM

MicroSafe H2S Gas Sensor

ALM ALM

FLT 1 2 CAL

PGM 2

Figure 3 Transmitter Module

TP-524D Instruction Manual Rev. 0.5 Page 2 of 36

Model TP-524D

Field Replaceable Sensor

The Detcon solid-state H2S gas sensor is a field proven, replaceable type sensor. It can be accessed and
replaced in the field by removing the wiring from the connector PCB, and unthreading the Sensor from the
junction box. The Detcon solid state H2S sensor has an infinite shelf life and is supported by a 10 year,
industry-leading warranty.

Figure 4 Field Replaceable H2S Sensor

NOTE: The Field Replaceable H2S Gas Sensor is constructed from 316 Stainless Steel in order to maximize
corrosion resistance in harsh environments.

Base Connector PCB
The base connector board is mounted in the Junction Box. The connector board includes Lug less terminal
connections for incoming power and MA output, and connections for the H2S Replaceable Sensor.

Wiring to

Customer

Wiring

Figure 5 Base Connector Board

H2S Sensor

TP-524D Instruction Manual Rev. 0.5 Page 3 of 36

Model TP-524D

2. Installation

2.1 ATEX Operational Guidelines for Safe Use

1. Install sensor only in areas with classifications matching with those described on the approval label.
Follow all warnings listed on the label.

DETCON, THE WOODLANDS, TEXAS, USA
MODEL TP-524D
RATED: 12-28VDC, 100 mA @ 24VDC

Serial #

Date Code

WARNING:Keep cover tight while circuits are Alive.
WARNING:Understand manual before operating

0035

SIRA 09ATEX1351X
II 2 G Ex d IIB +H2 T4
Tamb = -40°C to +60°C

detcon, inc.

DETCON, THE WOODLANDS, TEXAS, USA
MODEL TP-524D
RATED: 12-28VDC, 100 mA @ 24VDC

Serial #

Date Code

WARNING:Keep cover tight while circuits are Alive.
WARNING:Understand manual before operating

0035

SIRA 09ATEX1351X
II 2 G Ex d IIB +H2 T4
T amb = -20°C to +60°C

detcon, inc.

Figure 6 TP 524D ATEX Approval Labels

Detcon Condulets Killark Condulets

2. Ensure that the sensor is properly mounted in a vertical orientation with sensor facing down. Avoid
use of Teflon Tape, or any type of non-conductive pipe thread coating on the NPT threaded
connection.

3. Use ¾” NPT plugs properly rated for hazardous locations to block any unused connections

4. Removal of the Junction box cover or threaded sensor housing (399-800000-000) violates the Ex d
protection method and hence power must be removed from the sensor prior its safe removal.

5. Proper precautions should be taken during installation and maintenance to avoid the build-up of static
charge on the plastic components of the sensor. These include the splashguard and splashguard
adapter.

6. Do not operate the sensor outside of the stated operating temperature limits.

7. Do not operate the sensor outside the stated operating limits for voltage supply.

8. These sensors meet EN60079-0, EN60079-1.

2.2 Sensor Placement

Selection of sensor location is critical to the overall safe performance of the product. Five factors play an
important role in selection of sensor locations:

(1) Density of the gas to be detected
(2) Most probable leak sources within the industrial process
(3) Ventilation or prevailing wind conditions
(4) Personnel exposure
(5) Maintenance access
(6) Additional Placement Considerations

Density

Placement of sensors relative to the density of the target gas is such that sensors for the detection of heavier
than air gases should be located within 4 feet of grade as these heavy gases will tend to settle in low lying

TP-524D Instruction Manual Rev. 0.5 Page 4 of 36

Model TP-524D

Note:

NOTE:

areas. For gases lighter than air, sensor placement should be 4-8 feet above grade in open areas or in pitched
areas of enclosed spaces.

H2S is heavier than air.

Leak Sources

The most probable leak sources within an industrial process include flanges, valves, and tubing connections of
the sealed type where seals may either fail or wear. Other leak sources are best determined by facility
engineers with experience in similar processes.

Ventilation

Normal ventilation or prevailing wind conditions can dictate efficient location of gas sensors in a manner
where the migration of gas clouds is quickly detected.

Personnel Exposure

The undetected migration of gas clouds should not be allowed to approach concentrated personnel areas such
as control rooms, maintenance or warehouse buildings. A more general and applicable thought toward
selecting sensor location is combining leak source and perimeter protection in the best possible configuration.

Maintenance Access

Consideration should be given to providing easy access for maintenance personnel. Consideration should also
be given to the consequences of close proximity to contaminants that may foul the sensor prematurely.

In all installations the gas sensor should point straight down (refer to Figure 8).

Improper sensor orientation may result in false readings and permanent sensor damage.

Additional Placement Considerations

The sensor should not be positioned where it may be sprayed or coated with surface contaminating substances.
Painting sensor assemblies is prohibited.

Although the sensor is designed to be RFI resistant, it should not be mounted in close proximity to high­powered radio transmitters or similar RFI generating equipment.

When possible mount in an area void of high wind, accumulating dust, rain, or splashing from hose spray,
direct steam releases, and continuous vibration. If the sensor cannot be mounted away from these conditions
then make sure the Detcon Harsh Location Dust Guard accessory is used.

Do not mount in locations where temperatures will exceed the operating temperature limits of the sensor.
Where direct sunlight leads to exceeding the high temperature-operating limit, use a sunshade to help reduce
temperature.

2.3 Sensor Contaminants and Interference

Solid State H2S sensors may be adversely affected by exposure to certain airborne substances. Loss of
sensitivity or corrosion may be gradual if such materials are present in sufficient concentrations.

The more common materials that potentially cause problems with the sensors are as follows:

Silicone vapors such as those found in greases and lubricants

TP-524D Instruction Manual Rev. 0.5 Page 5 of 36

Model TP-524D

NOTE:

NOTE:

NOTE:

Halide Compounds containing Chlorine, Chlorine Dioxide, Fluorine, HF, HCl, and Bromine
Caustic and Acid liquids and concentrated vapors
Heavy metals such as tetraethyl lead
Heavy and complex VOC gasses

The presence of such contaminants in an area does not preclude the use of this H2S sensor technology,
although it is likely that the sensor lifetime will be shorter as a result. Use of this sensor in these environments
may require more frequent calibration checks to ensure safe system performance.

Solid State H2S sensors require O2in the background gas and the reading is affected by changing O2levels.

Interference Data

There are some gases typically found in industrial environments that can cause a cross-interference response
on the sensor. See the Table below for some examples.

Table 1 Cross Interference Gases

GAS PPM GAS PPM

Methane 25,000 = 0 Ammonia 500 = 1
Ethane 5,000 = 0 Diesel Fuel 1000 = 0
Hexane 5,000 = 0 Dimethyl Sulfide 4.4 = 0
Propane 5,000 = 0 Ethylene 200 = 0
Butane 5,000 = 0 Freon 12 1,000 = 0
Carbon Monoxide 1% = 0 Hydrogen 5% = 0
Carbon Dioxide 5,000 = 0 Methyl Mercaptan 10 = 0
Carbon Disulfide 14 = 0 Sulfur Dioxide 300 = 0
Methanol 500 = 5 Toluene 32 = 0
Isopropanol 500 = 3 Ethanol 500 = 5

The Detcon MOS Sensor Cell can be damaged to the point of non-functioning if the
unit is left off power and in the presence normal air levels of moisture for periods exceeding 8
hours.

Always protect the sensor cell with the Detcon Sealing Cap and a fresh desiccant
packet when the sensor is powered off, this will avoid permanent sensor cell damage and help
preserve the span calibration.

2.4 Mounting Installation

The TP-524D should be vertically oriented so that the sensor points straight downward. The explosion-proof
enclosure or junction box would then typically be mounted on a wall or pole (See Figure 7). Detcon provides
a selection of standard junction boxes in both Aluminum and Stainless Steel.

Do not use Teflon Tape or any other type of Pipe Thread material on the ¾” threads

unless the unit is mounted in a severe or harsh environment. Metal-on-metal contact must be
maintained to provide a solid electrical ground path. If Teflon Tape is used the Sensor must be
externally grounded using a ground strap.

When mounting on a pole, secure the Junction Box to a suitable mounting plate and attach the mounting plate
to the pole using U-Bolts. (Pole-Mounting brackets for Detcon Junction Box’s are available separately.)

TP-524D Instruction Manual Rev. 0.5 Page 6 of 36

6.125"

NOTE:

NOTE:

NOTE:

5.5"

PGM 1

MODEL TP-524DHOUSTON,TEXAS

3

NPT Ports

4

Model TP-524D

4.6"

6.45"

1

" mounting holes

4

2"

TM

MicroSafe H2S Gas Sensor

ALM ALM

FLT 1 2 CAL

PGM 2

2.1"

5.25"

8-32 tapped
ground point

H2S Sensor

Splash Guard

Wall (or other

mounting surface)

Figure 7 Typical Outline and Mounting Dimensions

2.5 Electrical Installation

The Sensor Assembly should be installed in accordance with local electrical codes. The sensor assemblies are
FM and CSA/NRTL approved (US and Canada) for Class I, Division 1, Groups B, C, & D area classifications.

Proper electrical installation of the gas sensor is critical for conformance to Electrical Codes and to avoid
damage due to water leakage. Refer to Figure 8 and Figure 9 for proper electrical installation.

If a conduit run exits the secondary port, repeat the installation technique shown in

Figure 8.

In Figure 8, the drain allows H2O condensation inside the conduit run to safely drain away from the sensor
assembly. The electrical seal fitting is required to meet the National Electrical Code per NEC Article 500-3d
(or Canadian Electrical Code Handbook Part 1 Section 18-154). Requirements for locations of electrical seals
are covered under NEC Article 501-5. Electrical seals also act as a secondary seal to prevent water from
entering the wiring terminal enclosure. However, they are not designed to provide an absolute watertight seal,
especially when used in the vertical orientation.

A conduit seal is typically required to be located within 18" of the J-Box and Sensor

Assembly. Crouse Hinds type EYS2, EYD2 or equivalent are suitable for this purpose.

The Detcon Warranty does not cover water damage resulting from water leaking into

the enclosure.

TP-524D Instruction Manual Rev. 0.5 Page 7 of 36

Conduit

NOTE:

NOTE 1:

NOTE 2:

Model TP-524D

"T"

Drain

EYS Seal Fitting

PGM 1

MODEL TP-524D

HOUSTON,TEXAS

TM

MicroSafe H2S Gas Sensor

ALM ALM

FLT 1 2 CAL

PGM 2

Figure 8 Typical Installation

Any unused ports should be blocked with suitable ¾” male NPT plugs. Detcon
supplies one ¾” NPT male plug with each J-box enclosure. If connections are other than ¾”
NPT, use an appropriate male plug of like construction material.

2.6 Field Wiring

Detcon Model TP-524D solid-state H2S sensor assemblies require three conductor connections between power
supplies and host electronic controller’s 4-20mA output. A 250 ohm load resistor is needed on the 4-20 mA
line when it is not being used. Wiring designations are DC+, DC-, MA (sensor signal). The maximum wire
length between sensor and 24VDC source is shown in the Table below. The maximum wire size for
termination in the Junction Box is 14 AWG.

Table 2 Wire Gauge vs. Distance

AWG Wire Dia. Meters Feet

22 0.723mm 700 2080 3A
20 0.812mm 1120 3350 5A
18 1.024mm 1750 5250 7A
16 1.291mm 2800 8400 10A
14 1.628mm 4480 13,440 20A

Wiring table is based on stranded tinned copper wire and is designed to serve as a

reference only.

Shielded cable is required for installations where cable trays or conduit runs include
high voltage lines or other possible sources of induced interference. Separate conduit runs are
highly recommended in these cases.

Over-Current

Protection

TP-524D Instruction Manual Rev. 0.5 Page 8 of 36