4.Service and Maintenance............................................................................................................................20
4.1Replacement of Plug-in Sensor......................................................................................................... 20
4.2Replacement of ITM......................................................................................................................... 21
4.3Replacement of the Model 100 Terminal Board............................................................................... 21
Figure 1 Sensor Assembly with Optional J-Box and LED Display..................................................................... 1
Figure 2 Construction of Electrochemical Toxic Sensor...................................................................................... 1
Figure 3 Construction of Galvanic Cell................................................................................................................ 2
Figure 7 DM Standard Terminal Board................................................................................................................ 4
Figure 8 Model 100 Display Terminal Board ...................................................................................................... 4
Figure 9 Model 100 Series Display...................................................................................................................... 5
Table 2 Model 100 Terminal Board Jumper ...................................................................................................... 11
Table 3 Sensor Specific Data .............................................................................................................................29
Detcon Model DM-100 toxic gas and O2deficiency sensors are non-intrusive 4-20mA loop powered sensors
designed to detect and monitor a wide range of toxic gases in the air. Ranges of detection for toxic gases are 01ppm up to 0-10,000ppm; typical ranges of detection are 0-10ppm, 0-25ppm, 0-50ppm and 0-100ppm. Ranges
for O2deficiency are 0-1% up to 0-25% by volume.
The basic sensor assembly consists of an electrochemical fuel cell mounted in Intrinsically Safe stainless steel
housing and includes a Splash Guard Cal Adapter. Optionally, the sensor can be installed on an explosion
proof junction box with a Model 100 Terminal Board and may include a Model 100 Loop Powered LED
display. Other options are available, contact Detcon for more information.
Model 100
DETCON,INC.
DM-100
H2S
100PPM
Figure 1 Sensor Assembly with Optional J-Box and LED Display
Electrochemical Sensor Technology
The DM-100 toxic gas sensors are based on electrochemical cells. Each cell consists of three electrodes
embedded in an electrolyte solution all housed beneath a diffusion membrane. Sensitivity to specific target
gases is achieved by varying composition of any combination of the sensor components. Good specificity is
achieved in each sensor type. The cells are diffusion limited via small capillary barriers resulting in a long
service life of up to three or more years. The electrochemical cell is packaged as a field replaceable plug-in
sensor.
Figure 2 Construction of Electrochemical Toxic Sensor
DM-100 Instruction ManualRev. 3.3Page 1 of 40
Model DM-100
The DM-100 O2deficiency sensor technology is a two electrode galvanic metal air battery type cell, which is
housed as a field replaceable intelligent plug-in sensor. The cell is diffusion limited and functions as a direct
current generator proportional to the amount of oxygen adsorption. The sensors are temperature compensated
and show good accuracy and stability over the operating temperature range of -20° to 50°C (-4° to +122° F).
The sensor is warranted for two years and has an expected service life of up to 2.5 years in ambient air at
20.9% oxygen.
Figure 3 Construction of Galvanic Cell
1.2Modular Mechanical Design
The Model DM-100 Sensor Assembly is completely modular and is made up of four parts (Figure 4):
1. DM-100 Intelligent Transmitter Module (ITM)
2. Intelligent Plug-in Sensor (varies by gas type and range)
3. 100 Series Bottom Housing Assembly (H2S assemblies use 100 Series Bottom Housing Assembly
with Integral Filter)
4. Splash Guard.
100 Series Bottom
Housing Assembly
Splash Guard
Housing Bottom
Locking Screw
O-Ring
Plug-in
Replaceable
Sensor
Programming
100 PPM
H2S
Magnetic
Switches
3
" NPT Locking Nut
4
DM-100
DETCON, INC.
Intelligent Transmitter Module (ITM)
Micro-processor controlled circuit
encapsulated in an Explosion proof
housing.
Interconnect
Wires
Figure 4 Sensor Assembly Breakaway
NOTE
DM-100 Instruction ManualRev. 3.3Page 2 of 40
All metal components are constructed from electro polished 316 Stainless Steel in order to
maximize corrosion resistance in harsh environments.
Model DM-100
RS-485
Safe Barrier
DM-100 Intelligent Transmitter Module
The Transmitter Module is a microprocessor-based package that is attached to the explosion proof junction
box.
Circuit functions include;
an intrinsically safe barrier,
on-board power supply,
microprocessor,
magnetic programming switches,
and a linear 4-20mA DC output.
Magnetic program switches located on either side of the ITM are activated via a hand-held magnetic
programming tool, thus allowing non-intrusive operator interface with the Transmitter Module. Electrical
classifications are Class I, Division 1, Groups A, B, C, and D.
Intrinsically
RS-485 Port
Analog 4-20mAOut
Power In
Plug-In
Sensor
Micro-
Processor
4-20mA
Loop
Power
I/O
Circuit
Protection
Figure 5 Functional Block Diagram
Field Replaceable Sensor
The Detcon family of electrochemical gas sensors is field proven, plug-in sensors with over-sized gold-plated
connections that eliminate corrosion problems. The sensor can be accessed and replaced in the field easily by
releasing the locking screw and unthreading the Splash Guard Adapter. Detconꞌs family of toxic sensors has a
long shelf life and is supported by an industry-leading warranty (Section 7).
Figure 6 Plug-in Sensor
DM-100 Instruction ManualRev. 3.3Page 3 of 40
Model DM-100
1.3Model 100 Standard Terminal Board (Optional)
If the sensor is ordered with an explosion proof condulet/junction box, the sensor will come with the Model
100 Standard Terminal Board mounted in the J-Box (Figure 7). This terminal board affords the user easy plugin connectors for use in wiring the unit during installation, and convenient test points for measuring the
milliamp (mA) output.
Customer
Wiring
Figure 7 DM Standard Terminal Board
V+
mA
RED
Sensor Wiring
WHITE
GREEN
BLUE
The standard terminal board provides an easy Digital Volt Meter (DVM) connection for reading the mA output
from the sensor. Two test points (TP1 and TP2) provide a connection across a 10Ω resistor that develops a
10mV voltage drop per 1mA output. Thus a reading of 40mV on a DVM equals 4mA of current. This is an
alternative method to reading the mA output of the sensor for assemblies that do not include the DM-100
Series Display option. Refer to Section 2.6, Field Wiring for more information about the setup of the DM-100
Terminal Board.
1.4DM-100 Display Terminal Board (Optional)
If the unit is ordered with the optional display or a battery pack (wireless configurations) the unit comes with
the DM-100 Display Terminal Board mounted in the J-Box (Figure 8).
Customer Wiring
mA
WIRELESS
PROGRAM
J2
J7
J6
POWER IN
( SOLAR)
AIN2MAGND
24V
SENSOR
POWER
PWR
A
B
GND
MODBUS OUT
( WIRELESS)
B
A
24V
GND
MODBUS IN
PROGRAM
WIRELESS
W/BK
W/BN
W/BU
W/GN
W/V
AIN1
J8
SW2
24V
GND
J1
J4
SW1
A
B
J5
TERM
GND
PWR
L9
SCL
DISPLAY
JP1
SP1
SP2
SDA
WHITE
BLACK
BLUE
RED
Figure 8 Model 100 Display Terminal Board
DM-100 Instruction ManualRev. 3.3Page 4 of 40
Model DM-100
JP1
This terminal board includes connectors for the following:
Table 1 Terminal Board Connectors
TerminalConnectorPurpose
J14-Pin ConnectorModbus Out (Wireless Transceiver Option)
J26-Pin HeaderWireless Transceiver Programming Header
J36-Beau ConnectorBattery operation or display interface dependent on sensor configuration
J44-Pin ConnectorModbus In
J56-Pin ConnectorDisplay interface with battery/wireless configurations
J64-Pin ConnectorSensor connections
J74-Pin ConnectorAuxiliary power in and mA out
J86-Pin ConnectorWireless Transceiver
J95-Pin HeaderTerminal Board Programming
The Model 100 Display Terminal Board does not provide test points for measuring the milliamp (mA) output.
The mA output is available at J7.
NOTE
Install JP1 jumper on pins 1 and 2 if a battery pack is used. Install
battery is not used.
on pins 2 and 3 if
1.5DM-100 Series Display (Optional)
The DM-100 Series Display is a 4-digit LED display that provides a direct display of the sensor readings. In
units that are ordered with the optional display, the display is mounted directly onto the J3 Beau connector of
the Display Terminal Board so the display can be easily seen through the J-box window. The display
automatically identifies the ITM, the sensor type, and range. This factory installed option must be ordered with
the sensor assembly.
Figure 9 Model 100 Series Display
1.6Wireless Transceiver and Battery Pack (Optional)
The DM-100 has the option to operate on a wireless network with the addition of a wireless transceiver and
battery pack. These options allow the sensor to be remotely mounted without the need for cables. These
options are factory installed. Contact Detcon for more information on these options.
DM-100 Instruction ManualRev. 3.3Page 5 of 40
Model DM-100
2.Installation
2.1 Hazardous Locations Installation Guidelines for Safe Use
1. Install the sensor only in areas with classifications matching the approval label. Follow all warnings
listed on the label.
Figure 10 Approval Label
2. For intrinsically safe Ex ia installations, follow the intrinsically safe installation guidelines shown in
control drawing #3993, Section 8.5.
3. For non-intrinsically safe Ex mb [ib] installations, ensure that the sensor is properly threaded into a
suitable explosion-proof rated junction box with a downward pointing female3/4" NPT threaded
connection. The sensor should be threaded at least 5 full turns until tight, with the locking screw
facing forward. Avoid use of Teflon Tape, or any type of non-conductive pipe thread coating on the
NPT threaded connection.
4. A good ground connection should be verified between the sensor’s metal enclosure and the junction
box. If a good ground connection is not made, the sensor can be grounded to the junction box using
the sensor’s external ground lug. Verify a good ground connection between the junction box and earth
ground.
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 (Splash Guard and Splash Guard adapter).
6. All input circuits of the DM-100 must be connected to current limiting devices (e.g. Fuses of 1500
amp breaking capacity) to ensure that the maximum input current does not exceed 62mA.
7. Do not substitute components. Substitution of components may impair the intrinsic safety rating.
8. Do not operate the sensor outside of the stated operating temperature limits.
9. Do not operate the sensor outside the stated operating limits for voltage supply.
10. These sensors meet ATEX standards EN60079-0, EN60079-18 and EN60079-11.
11. These sensors have a maximum safe location voltage of Um=60V.
12. These sensors pass dielectric strength of 500VRMS between circuit and enclosure for a minimum of 1
minute at a maximum test current of 5mA.
DM-100 Instruction ManualRev. 3.3Page 6 of 40
Model DM-100
13. The DM-100 may be used as an oxygen deficiency sensor; the DM-100 must not be used for detecting
oxygen concentrations expected to be greater than 21%.
14. The DM-100 must only use gas sensor cell models 371-xxxxxx-xxx (Table 5, Section 8.1). No other
gas sensor cells shall be used.
2.2Sensor Placement
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
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
areas. For gases lighter than air, sensor placement should be 4 to 8 feet above grade in open areas or in pitched
areas of enclosed spaces.
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 and the consequences of
close proximity to contaminants that may foul the sensor prematurely.
NOTE
In all installations the gas sensor should point straight down (Figure 12). 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.
DM-100 Instruction ManualRev. 3.3Page 7 of 40
Model DM-100
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 ensure 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.
2.3Sensor Contaminants and Interference
Electrochemical toxic gas may be adversely affected by exposure to other airborne gases. Depending on the
cross-sensitivity relationship, there may be a positive or negative impact on the reading.
The most commonly present gases that potentially cause interference problems are listed in Table 4,
Interfering Gases and Table 5, Cross Interference Table (Section 8.3, Interference Table).
The presence of cross-interference gases in an area does not preclude the use of this sensor technology. The
sensor could experience a false high or false low reading should exposure occur.
Cross-Interference Data Table
The gases typically found in industrial environments that may cause a cross-interference response on Detcon
toxic gas sensors are listed in Table 5 (Section 8.3, Interference Table). Review Table 5 for the correct gas and
then scan across the list for possible interference gases. Determine the magnitude of cross-interference that
may occur.
2.4Sensor Mounting
The DM-100 should be vertically oriented so that the sensor points straight downward. The explosion-proof
enclosure or junction box is typically mounted on a wall or pole (Figure 11). Detcon provides a selection of
standard junction boxes in both Aluminum and Stainless Steel.
If wall mounting without a mounting plate, make sure to use at least 0.5" spacers
NOTE
NOTE
underneath the J-Box’s1/4" mounting holes to move the wireless sensor assembly away
from the wall and allow access clearance to the sensor assembly.
Do not use Teflon Tape or any other type of Pipe Thread material on the3/4" threads unless
the sensor 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.
DM-100 Instruction ManualRev. 3.3Page 8 of 40
Model DM-100
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.)
1
4
13.75" Typ.
" mounting holes
6.1"
5.5"
DETCON,INC.
DM-100
H2S
100 PPM
3
NPT Ports
4
8-32 tapped
ground point
9.625" Typ.
Use spacersto move
sensor assembly away
from wallat least 0.5".
ITM Assembly
Splash GuardAdapter
4.35"
Spacer
Wall (or other
mounting surface)
2"
Splash Guard
Figure 11 Typical DM-100 Sensor Assembly and Mounting Dimensions
2.5Electrical Installation
The Sensor Assembly should be installed in accordance with local electrical codes. The sensor assemblies are
CSA/NRTL approved (US and Canada) for Class I, Division 1, Groups A, B, C, & D area classifications, and
are ATEX Approved for Class I, Zone 1, Group IIC 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 12 for proper electrical installation.
NOTE
In Figure 12, 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 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.
If a conduit run exits the secondary port, repeat the installation technique shown in
Figure 12.
DM-100 Instruction ManualRev. 3.3Page 9 of 40
Model DM-100
NOTE
NOTE
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.
Conduit
"T"
Drain
EYS Seal Fitting
Model1 00
DETCON,INC.
DM-100
100PPM
H2S
Figure 12 Typical Installation
Any unused ports should be blocked with suitable3/4" male NPT plugs. Detcon supplies one
3
NOTE
/4" NPT male plug with each J-box enclosure. If connections are other than3/4" NPT, use
an appropriate male plug of like construction material.
2.6Field Wiring
Detcon Model DM-100 sensor assemblies require two conductor connections between power supplies and host
electronic controller’s 4-20mA input. Wiring designations are PWR and mA (sensor signal).
Shielded cable is required for installations where cable trays or conduit runs include high
NOTE
NOTE
Terminal Connections – with Junction Box Option
CAUTION
voltage lines or other possible sources of induced interference. Separate conduit runs are
highly recommended in these cases.
The supply of power should be from an isolated source with over-current protection.
Do not apply System power to the sensor until all wiring is properly terminated.
Refer to Section 2.7, Initial Start Up.
DM-100 Instruction ManualRev. 3.3Page 10 of 40
Model DM-100
1. Remove the junction box cover.
2. If the sensor has the Display option installed, unplug the display from the terminal board by pulling the
display out of the junction box. The display option plugs directly into the terminal board’s Beau
Connector.
3. Observing correct polarity, terminate the 2-conductor power and 4-20mA field wiring (+ and mA) at the
terminal board connector J1 (4-20mA Out) on the Standard Terminal Board shown in Figure 7, or J7
(PWR and MA) on the Display Terminal Board shown in Figure 8.
4. Trim and cap all exposed wire leads if they are not permanently landed in the terminal board.
5. The sensor should be connected to J2, labeled SENSOR on the Standard Terminal Board, and J6, labeled
SENSOR, on the Display Terminal Board. On the Standard Terminal Board, the wiring from the sensor
should match the silkscreen on the terminal board: R–Red, BK–Black, GN-Green, BU–Blue, and W–
White. On the Display Terminal Board the wiring should be: Red-PWR, Black-GND, White–A, Blue–B
(Green is not connected).
6. On the Display Terminal Board other connectors are provided for factory installed options. The options
ordered will dictate if, and what connectors are used. The display option is plugged into the Beau
connector (J3) for a DM-100 with just the display option added. Other options are covered in the
associated manual for those options.
7. If a display was removed in Step 2, re-install the display by plugging it back into the terminal board.
8. Replace the junction box cover after initial startup.
A 6-32 or 8-32 threaded exterior ground point is provided on most junction boxes for an
NOTE
external ground. If the Sensor Assembly is not mechanically grounded, an external ground
strap must be used to ensure that the sensor is electrically grounded.
2.6.1DM-100 Display Terminal Board Settings
The Model 100 Display Terminal Board contains a jumper that must be configured properly for the board to
operate correctly. The jumper is normally configured at the factory and should not be changed. Misplacement
of the jumper may cause the sensor to become inoperative.
Table 2 Model 100 Terminal Board Jumper
JP11-2 – Battery installed2-3 – Display only
2.7Initial Start Up
2.7.1Toxic Gas Sensors
Upon completion of all mechanical mounting and termination of all field wiring, apply system power in the
range of 11-26VDC (24VDC typical) and observe the following normal conditions:
1. If the Loop Powered Display option is installed, the display should read 0.0 upon power up. If a Loop
Powered Display is not installed on the sensor, set a DVM to measure millivolts, and connect it across
TP1 and TP2 on the terminal board. The DVM will read the voltage drop across a 10Ω resistor. The
resistor develops a 10mV voltage drop per 1mA of current. Thus a reading of 40mV on a DVM equals
4mA of current.
DM-100 Instruction ManualRev. 3.3Page 11 of 40
Model DM-100
2. A temporary upscale reading may occur as the sensor stabilizes. This upscale reading will decrease to
"0" ppm (40mV on the DVM) within 1 to 2 minutes of power-up, assuming there is no gas in the area
of the sensor.
NOTE
The 4-20mA signal is held constant at 4mA for the first two minutes after power up.
3. Sensors cells that use a bias voltage require a longer time to stabilize. This can vary between 1 and 24
hours depending on the sensor type and range. Biased sensors include NH3, NO, HCl, and VOC gases
(ethylene oxide, ethylene, methanol, formaldehyde….etc).
Initial Operational Tests
After a warm up period of 1 hour (or when zero has stabilized), the sensor should be checked to verify
sensitivity to the target gas.
Material Requirements
Detcon PN 613-120000-700 700 Series Splash Guard with integral Cal Port and Calibration Wind
Guard (P/N 943-000000-000) -OR-
Detcon PN 943-000006-132 Threaded Calibration Adapter - OR -
Detcon PN 943-01747-T05 Teflon Calibration Adapter for highly reactive gases
Detcon Span Gas; 50% of range target gas in balance N2 or Air at fixed flow rate between
200-500cc/min (500cc/min is preferred)
DVM (if a loop powered display is not installed)
NOTE
Calibration gas generators using perm tubes or electrochemical sources may be used in
place of span gas cylinders.
NOTE
The cover of the junction box will need to be removed if there is not a loop powered
display. The area may need to be de-classified.
1. If the sensor has a loop power display installed, the display should read "0". If a DVM is used to
measure the 4-20mA output, set the DVM to measure millivolts and connect the leads across TP1 and
TP2 on the terminal board. The DVM should read 40±2mV.
2. Attach the calibration adapter to the Splash Guard adapter or connect tubing to integral cal port. It is
recommended that the Wind Guard (PN 943-000000-000) in installed over the Splash Guard during
calibration. Apply the test gas at a controlled flow rate of 200-500cc/min (500cc/min is the
recommended flow). If the sensor has a loop power display attached the reading should increase to
50% of full range (if the range is 100, the display should read 50). Observe that the DVM increases to
a level near that of the applied calibration gas value. Typically this would be 50% of full range, a
reading of 120±2mV (12mA).
3. Remove test gas and observe that, if the sensor has a loop power display installed, the display
decreases to "0". If a DVM is used the DVM reading should decrease back to 40mV (4mA).
4. If a calibration adapter was used during these tests, remove them from the unit, and re-install the
Splash Guard. If the wind guard was used, remove the wind guard.
Initial operational tests are complete. DM-100 toxic gas sensors are factory calibrated prior to shipment, and
should not require significant adjustment on start up. However, it is recommended that a complete calibration
test and adjustment be performed 16 to 24 hours after power-up. Refer to zero and span calibration instructions
in Section 3.3, Calibration.
DM-100 Instruction ManualRev. 3.3Page 12 of 40
Model DM-100
2.7.2O2Deficiency Sensors
Upon completion of all mechanical mounting and termination of all field wiring, apply system power in the
range of 11-30VDC (24VDC typical) and observe the following normal conditions:
If the sensor has a loop power display installed, the display should read close to 20.9%. If a DVM is used to
measure the 4-20mA output, set the DVM to measure millivolts and connect the leads across TP1 and TP2 on
the terminal board. The DVM should read 173.7±2mV.
The reading should stabilize within 1 to 2 minutes of power-up (assuming a ‘normal’ ambient O
concentration).
Initial Operational Tests
After a warm-up period of 5 minutes the sensor should be checked to verify response to O2deficiency.
Material Requirements
Detcon PN 613-120000-700 700 Series Splash Guard with integral Cal Port and Calibration Wind
Guard (P/N 943-000000-000) -OR-
Detcon PN 943-000006-132 Threaded Calibration Adapter - OR -
Detcon PN 943-01747-T05 Teflon Calibration Adapter for highly reactive gases
Detcon Zero Gas: 100% N2 at fixed flow rate of 200-500cc/min
DVM (if a loop powered display is not installed)
NOTE
The cover of the junction box will need to be removed if there is not a loop powered
display. The area may need to be de-classified.
1. Attach the calibration adapter to the threaded sensor housing or connect tubing to the integral cal port.
Apply the test gas at a controlled flow rate of 200-500cc/min (500cc/min is the recommended flow).
2. If the sensor has a loop power display installed, the display reading should drop to "0". If a DVM is
used to measure the 4-20mA output, set the DVM to measure millivolts and connect the leads across
TP1 and TP2 on the terminal board. The DVM should read 40±2mV.
2
3. Remove test gas and calibration adapter. If the sensor has a loop power display installed, the display
should return to a reading of 20.9%. The DVM should return to a reading of 173.7mV (17.37mA).
Initial operational tests are complete. DM-100 O2deficiency sensors are factory calibrated prior to shipment,
and should not require significant adjustment on start up. A complete calibration test and adjustment should be
performed 16 to 24 hours after power-up. Refer to zero and span calibration instructions in Section 3.3,
Calibration.
DM-100 Instruction ManualRev. 3.3Page 13 of 40
Model DM-100
3.Operation
The Operator Interface of the Model 100 Series gas sensors is accomplished via two internal magnetic
switches located on the left and the right of the sensor (Figure 14). The two switches, labeled PGM1 and
PGM2, allow for complete calibration of the sensor. The addition of the Loop Powered Display allows the
ability to calibrate the sensor without the need to de-classify the area or the use of hot permits.
Figure 13 Magnetic Programming Tool
The magnetic programming tool (Figure 13) is used to operate the magnetic switches. Switch action is defined
as momentary contact and 3-second hold. Hold time is defined as the time from the point when the magnet is
placed in close proximity with the switch. For momentary contact the programming magnet is briefly held
over a switch location. The location of PGM1 and PGM2 are shown in Figure 14.
Program 1
DETCON, INC.
DM-100
H2S
100 PPM
Figure 14 Magnetic Programming Switches
Program 2
3.1Normal Operation
In normal operation, the mA output will be the current sensor reading. In normal operation, the 4-20mA
current output linearity corresponds with the full-scale range. If the DM-100 Display option is added to the
sensor, the display continuously shows the current sensor reading in ppm or % by volume, which will
normally appear as "0". If the sensor is actively experiencing any diagnostic faults, the mA output will be
taken to 1.2mA to designate a fault to the controller. The DM-100 Display will display an error code to signify
a fault. Error codes are noted by Fxx, where F is Fault and xx is an error code. Error codes are defined in
Section 5, Troubleshooting Guide .
3.2Auto Span Level Adjustment
This procedure can only be achieved if the unit has a display.
1. In normal operation, hold the programming magnet over PGM2 for a minimum of 3 seconds to set the
Auto span level.
DM-100 Instruction ManualRev. 3.3Page 14 of 40
Model DM-100
2. SET AUTO SPAN will scroll across the display to indicate entry into the routine.
3. When adjustments can be made, the display will scroll ADJUST AUTO SPAN. Swipe PGM2 to
adjust the AutoSpan Level up. Swipe PGM1 to adjust it down.
4. If no action is taken within 5 seconds, the display will scroll AUTO SPAN NOT SAVED to indicate
a value was not saved. The unit will then return to normal operation.
5. If changes are made, the display will reflect the adjustments.
6. A 2 second hold on PGM1 or PGM2 will save the level. The display will scroll AUTO SPANSAVED to indicate that the value was saved and the unit will return to normal operation.
7. If no hold is placed on PGM1 or PGM2, the level will revert to the previous value. The display will
scroll AUTO SPAN NOT SAVED to indicate that the value was not saved and the unit will return to
normal operation.
3.3Calibration
Zero and span calibration should be performed on a routine basis (quarterly minimum) to ensure reliable
performance. If a sensor has been exposed to any de-sensitizing gases, or to very high over-range combustible
gas levels, re-calibration should be considered. Unless otherwise specified, span adjustment is recommended at
50% of the full scale range.
3.3.1Zero Calibration
The zero calibration is used to zero the sensor. Zero calibration should be performed periodically or as
required. Zero calibration should be considered after periods of over-range target gas exposure. Local ambient
air can be used to zero calibrate a toxic gas sensor as long as it can be confirmed that it contains no target or
interference gases. If this cannot be confirmed then a zero air or N2cylinder should be used. Pure N2must be
used for zero calibration of the O2deficiency sensors.
Material Requirements:
Detcon PN 327-000000-000 Programming Magnet
Detcon PN 613-120000-700 700 Series Splash Guard with integral Cal Port and Calibration Wind
Guard (P/N 943-000000-000) -OR-
Detcon PN 943-000006-132 Threaded Calibration Adapter - OR -
Detcon PN 943-01747-T05 Teflon Calibration Adapter for highly reactive gases
Detcon PN 942-001123-000 Zero Air cal gas (or use ambient air if no target gas is present).
Detcon PN 942-640023-100 Nitrogen 99.99%
DVM (if a loop powered display is not installed)
NOTE 1:
NOTE 2:
The zero gas source may be zero air or N2for toxic sensors, but must be pure N2(99.99%)
for O2deficiency sensors.
The Calibration Wind Guard must be used when the Splashguard Adapter with integral Cal
Port is used.Failure to use the Calibration Wind Guard may result in an inaccurate
AutoZero calibration.
NOTE 3:
DM-100 Instruction ManualRev. 3.3Page 15 of 40
The cover of the junction box will need to be removed if there is not a loop powered
Model DM-100
For O2 deficiency sensors
For O2 deficiency sensors
display. The area may need to be de-classified.
3.3.1.1 Display Not Installed
1. If a DM-100 Display is not installed on the sensor, set a DVM to measure millivolts, and connect it
across TP1 and TP2 on the terminal board. The DVM will read the voltage drop across a 10Ω resistor.
The resistor develops a 10mV voltage drop per 1mA of current. Thus a reading of 40mV on a DVM
equals 4mA of current.
2. For toxic sensors, if the ambient air is known to contain no target gas content, then it can be used for
zero calibration. If a zero gas cal cylinder is going to be used, attach the calibration adapter and set
flow rate of 200-500cc/min (500cc/min is the recommended flow rate) and let the sensor purge for 1 to
2 minutes before zeroing the sensor. For O2deficiency sensors, apply N2at a set flow rate of
500cc/min for 3 to 5 minutes before zeroing the sensor.
NOTE:
a time period of 3 to 5 minutes to successfully zero calibrate the sensor.
N2 (99.99%) MUST be applied at a flow rate of 500cc/min for
3.From Normal Operation, hold the programming magnet over PGM1 for 3 seconds. The reading will
dip momentarily to 2mA (20mV on the meter). The reading will then return to 4ma. (The ideal reading
for zero is 4.03mA or 40.3mV.)
4. Observe the reading for a minute or so to ensure that the reading does not drift.
5. If zero gas was used, remove the gas from the sensor.
3.3.1.2 With Display
1. For toxic sensors, if the ambient air is known to contain no target gas content, then it can be used for
zero calibration. If a zero gas cal cylinder is going to be used, attach the calibration adapter and set
flow rate of 200-500cc/min (500cc/min is the recommended flow rate) and let the sensor purge for 1 to
2 minutes before zeroing the sensor. For O2deficiency sensors, apply N2at a set flow rate of
500cc/min for 3 to 5 minutes before zeroing the sensor.
NOTE:
a time period of 3 to 5 minutes to successfully zero calibrate the sensor.
N2 (99.99%) MUST be applied at a flow rate of 500cc/min for
2. From Normal Operation, hold the programming magnet over PGM1 for 3 seconds. The display will
scroll 1-ZERO…2-SPAN for 10 seconds.
NOTE
3. Hold PGM1 to start Auto Zero routine, ZERO IN PROGRESS… will scroll across the display. Output
current from the sensor will drop to 3.5mA.
4. Observe the reading for a minute or so to ensure that the reading does not drift.
5. If zero gas was used, remove the gas from the sensor.
DM-100 Instruction ManualRev. 3.3Page 16 of 40
If no action is taken unit returns to normal operation after time expires, 10 seconds.
Model DM-100
3.3.2Span Calibration
Span Calibration is used to adjust the span of the sensor and should be performed periodically or as required.
Span calibration should be considered after periods of over-range target gas exposure. Unless otherwise
specified, span adjustment is recommended at 50% of range.
Material Requirements:
Detcon PN 327-000000-000 Programming Magnet
Detcon PN 613-120000-700 700 Series Splash Guard with integral Cal Port and Calibration Wind
Guard (P/N 943-000000-000) -OR-
Detcon PN 943-000006-132 Threaded Calibration Adapter - OR -
Detcon PN 943-01747-T05 Teflon Calibration Adapter for highly reactive gases
Detcon Span Gas (See Detcon for Ordering Information). Recommended span gas is 50% of range
with target gas. Other suitable span gas sources containing the target gas in air or N2 balance are
acceptable.
DVM (if a loop powered display is not installed)
NOTE 1;
The cover of the junction box will need to be removed if there is not a loop powered
display. The area may need to be de-classified.
A target gas concentration of 50% of range is strongly recommended. This should be
NOTE 2:
applied at a controlled flow rate of 200 to 500cc/min, with 500cc/min being the
recommended flow rate. Other concentrations can be used if they fall within allowable
levels of 10% to 100% of range.
The Calibration Wind Guard must be used when the Splashguard Adapter with integral Cal
NOTE 3:
Port is used.Failure to use the Calibration Wind Guard may result in an inaccurate
AutoZero calibration.
NOTE 4:
NOTE 5:
NOTE 6:
Contact Detcon for ordering information on Span Gas cylinders.
Ambient air should be used to calibrate O2 deficiency sensors as long as the oxygen
concentration is confirmed to be 20.9%.
Cross-calibration for span by use of other gases is not advised and should be confirmed by
Detcon.
Span consists of applying the correct gas concentration at the correct flow rate, and adjusting the sensor for the
proper output. The recommendation for span gas concentration is 50% of range. If a span gas containing the
recommended concentration is not available, other concentrations may be used as long as they fall between
10% and 100% of range.
3.3.2.1 Display Not Installed
1. Set a DVM up to measure millivolts, and connect it across TP1 and TP2 on the terminal board. The
DVM will read the voltage drop across a 10Ω resistor. The resistor develops a 10mV voltage drop per
1mA of current. Thus a reading of 40mV on the DVM equals 4mA of current.
2. Install the Calibration Wind Guard, or the appropriate calibration adapter.
DM-100 Instruction ManualRev. 3.3Page 17 of 40
Model DM-100
For O2 deficiency sensors
,
For O2 deficiency sensors
,
3. From normal operation, hold the programming magnet over PGM2 for at least 3 seconds. Apply the
span calibration test gas for toxic gas sensors at a flow rate of 200-500cc/min (500cc/min is the
recommended flow rate). The DVM reading will remain at 2mA or "0" for 2 minutes.
4. When the 2 minute wait is complete, the reading will increase to a level that corresponds to the level
of gas the plug-in sensor is detecting. There is a 30 second period to decide if the reading needs to be
adjusted. If the reading matches the level of gas applied continue to Step 7.
5. To adjust the reading, hold the programming magnet over PGM2. The reading will also start to
increase. Continue to hold the programming magnet over PGM2 to make the current increase, or hold
the magnet over PGM1 to make the current decrease. Use PGM1 and PGM2 to adjust the output to
match the target gas set-point. Assuming 50% of full range was applied, adjust the reading to 12mA
(120mV on the DVM).
12mA and 50% of full range are based on the use of a span gas concentration of 50%. If a
NOTE
different concentration of span gas is used, the mA reading will need to be calculated. I.E. if
a 25% concentration span gas is used the reading would be 8mA. Use the magnetic tool to
adjust the mA reading to the target set-point.
6. When the correct adjustment has been made, wait 15 seconds without holding the programming
magnet over either PGM1 or PGM2. The reading will momentarily decrease about 20% and then
return to the target reading. This indicates that the span calibration point has been successfully saved.
If a lack of proper signal level change is internally detected the sensor will immediately go into fault.
The reading will go to 1.2ma (12mV). Only a successful re-calibration will clear this fault (Section 5,
Troubleshooting Guide).
N2 (99.99%) MUST be applied at a flow rate of 500cc/min for
NOTE:
2 to 3 minutes until the sensor reading clears below 2.5% volume O2. At this point the
autospan cycle is complete. If not done properly a clearing fault will occur.
7. Remove the span gas and calibration adapter (or calibration wind guard), or for O2deficiency sensors,
apply N2at a set flow rate of 500cc/min. On the DVM, the reading will fall from the reported span
level to 4mA (40mV). The sensor now allows 5 minutes for the reading to clear below 10% of full
scale range (5.6mA). If the reading does not meet the clearing test criteria the sensor will go into fault.
The reading will go to 1.2ma 12Mv). Only a successful re-calibration will clear this fault (Section 5,
Troubleshooting Guide).
N2 (99.99%) MUST be applied at a flow rate of 500cc/min for
NOTE:
2 to 3 minutes until the sensor reading clears below 2.5% volume O2. At this point the
autospan cycle is complete. If not done properly a clearing fault will occur.
8. Span calibration is complete. If the Splash Guard was removed for calibration, re-install the Splash
Guard.
NOTE
Any fault during the AutoSpan will cause the current output from the sensor to drop to
1.2mA (12mV).
3.3.2.2 Display Installed
1. Install calibration adapter or wind guard.
2. From Normal Operation, hold the programming magnet over PGM1 for 3 seconds. The display will
scroll 1-ZERO…2-SPAN.
DM-100 Instruction ManualRev. 3.3Page 18 of 40
Model DM-100
For O2 deficiency sensors
,
For O2 deficiency sensors
,
3. Hold PGM2 for three seconds and Auto span routine is executed and APPLY XXXXX UUU GGG is
scrolled across the display. Where XXXXX represent the auto span level, UUU represent the units (%
or PPM), and GGG represent the gas type. Output current from the sensor will drop to 3.5mA.
4. Apply the span calibration test gas for toxic gas sensors at a flow rate of 200-500cc/min (500cc/min is
the recommended flow rate). As the sensor signal begins to increase the display will switch to XX
reading as the ITM shows the sensor’s "as found" response to the span gas presented. If it fails to meet
the minimum in-range signal change criteria within 21/2minutes, the display will report a Range Fault
fault code and the ITM will return to normal operation, aborting the AutoSpan sequence. The ITM will
continue to report a Range Fault and will not clear the fault until a successful AutoSpan is completed.
5. Assuming acceptable sensor signal change, after 1 minute the reading will auto-adjust to the
programmed AutoSpan level. During the next 30 seconds, the AutoSpan sequence checks the sensor
for acceptable reading stability. If the sensor fails the stability check, the reading is re-adjusted back to
the AutoSpan level and the cycle repeats until the stability check is passed. Up to three additional 30second stability check periods are allowed before the display scrolls a Stability Fault fault code and
the sensor will return to normal operation, aborting the AutoSpan sequence. The sensor will continue
to report a Stability Fault and will not clear the fault until a successful AutoSpan is completed.
N2 (99.99%) MUST be applied at a flow rate of 500cc/min for
NOTE:
2 to 3 minutes until the sensor reading clears below 2.5% volume O2. At this point the
autospan cycle is complete. If not done properly a clearing fault will occur.
6. Remove the span gas source and calibration adapter, or for O2deficiency sensors, apply N2at a set
flow rate of 500cc/min. The display will toggle between reporting a live reading and "REMOVE
GAS" as it clears toward "0". When the reading clears below 10% of range, the display will scroll
Span Complete and will revert to normal operation. If the sensor fails to clear to less than 10% in less
than 5 minutes, a Clearing Fault fault code will be dispalyed and the sensor will return to normal
operation, aborting the AutoSpan sequence. The sensor will continue to report a Clearing Fault and
will not clear the fault until a successful AutoSpan is completed.
N2 (99.99%) MUST be applied at a flow rate of 500cc/min for
NOTE:
2 to 3 minutes until the sensor reading clears below 2.5% volume O2. At this point the
autospan cycle is complete. If not done properly a clearing fault will occur.
NOTE
Any fault during the AutoSpan will cause the current output from the sensor to drop to
3.25mA.
3.4Fault Diagnostic/Failsafe Feature
If the ITM should incur a fault, the ITM will drop the mA output to 1.2mA (without display) or 3.25mA (with
display). This can occur if the ITM;
detects a problem with the sensor,
detects that there is no sensor cell connected, or
detects an internal ITM fault.
The ITM will hold the fault current output until the problem is resolved. If the DM-100 Display is installed,
the display will show an error code. The error codes are defined in Section 5, Troubleshooting Guide.
DM-100 Instruction ManualRev. 3.3Page 19 of 40
Model DM-100
4.Service and Maintenance
Calibration Frequency
In most applications, monthly to quarterly span calibration intervals will assure reliable detection. However,
industrial environments differ. Upon initial installation and commissioning, close frequency tests should be
performed, weekly to monthly. Test results should be recorded and reviewed to determine a suitable
calibration interval.
Visual Inspection
The Sensor should be inspected annually:
Inspect the sensor for signs of corrosion, pitting, and water damage.
Remove the Splash Guard and inspected it for blockage, broken, cracked, or missing pieces.
For H2S Sensor assemblies, inspect DM-100 Bottom Housing Assembly with integral filter (PN 602-
003552-100) for blockage of filter material.
Inspect inside of the Junction Box for signs of water accumulation, signs of corrosion.
Check wiring to ensure there are no loose or pinched wires and all connections are clean and tight.
Condensation Prevention Packet
A moisture condensation prevention packet (PN 960-202200-000) should be installed in every explosion proof
Junction Box. The prevention packet will prevent the internal volume of the J-Box from condensing and
accumulating moisture due to day-night humidity changes. This packet provides a critical function and should
be replaced annually.
4.1Replacement of Plug-in Sensor
NOTE
NOTE
1. Use a1/8" Allen wrench to release the locking cap head screw that locks the ITM and Splash Guard
Adapter together.
NOTE
2. Unthread and remove the Splash Guard Adapter and Splash Guard from the ITM.
3. Gently pull the plug-in sensor out of the ITM. Orient the new plug-in sensor so that it matches with the
female connector pins. Use the alignment marks provided to assure alignment is correct. When
properly aligned, press the sensor in firmly to make the proper connection.
It is not necessary to remove power while changing the plug-in toxic gas sensor in order to
maintain area classification, since it is intrinsically safe.
Only replace the plug-in sensor with an authorized DM-100 family of gas sensors.
One turn will suffice. Do not remove cap head screw completely.
4. Thread the Splash Guard Adapter onto the ITM to a snug fit and tighten the locking cap head screw
using the1/8" Allen wrench. Reinstall the Splash Guard.
5. Check and perform zero calibration and span calibration as per Section 3.3, Calibration.
DM-100 Instruction ManualRev. 3.3Page 20 of 40
Model DM-100
4.2Replacement of ITM
1. Remove the power source to the sensor assembly. Disconnect all sensor wire connections at the
Junction Box Terminal Board taking note of the wire connections.
NOTE
2. Use a wrench and the wrench flats provided at the top section of the ITM and unthread the ITM until it
can be removed.
3. Use a1/8" Allen wrench to release the locking cap head screw that locks the ITM and Splash Guard
Adapter together (One turn will suffice - Do not remove setscrew completely).
4. Unthread and remove the Splash Guard Adapter and Splash Guard from the ITM. These will be reused with the new ITM.
5. Gently remove the plug-in toxic gas sensor from the old ITM and install it in the new ITM. Orient the
plug-in sensors so that it matches the female connector pins on the new ITM and press the sensor in
firmly to make proper connection.
6. Thread the Splash Guard Adapter onto the new ITM until snug, tighten the locking cap head screw and
reinstall Splash Guard.
7. Feed the sensor assembly wires through the3/4" female NPT mounting hole and thread the assembly
into the J-box until tight and the ITM faces toward the front access point. Use the locking nut to secure
the ITM in this position. Connect the sensor assembly wires to the terminal board inside the Junction
Box (Section 2.6).
It is necessary to remove power to the Junction box while changing the ITM in order to
maintain area classification.
8. Check and/or perform Zero Calibration and Span Calibration (Section 3.3, Calibration).
4.3Replacement of the Model 100 Terminal Board
1. Remove the power source to the sensor assembly.
NOTE
2. Remove the junction box cover and remove the Loop Powered Display, if one is installed.
3. Remove the power connector on the terminal board.
4. Unplug all other connectors from the terminal board, noting where they are plugged into.
5. Remove the four 6-32 screws holding the terminal board to the base of the junction box and remove
the terminal board.
6. Install the new terminal board using the four 6-32 screws removed in Step 5.
7. If the unit has the DM-100 Display Terminal Board, ensure that the jumper on the terminal board is set
properly (Section 2.6.1, DM-100 Display Terminal Board Settings).
It is necessary to remove power to the Junction Box while changing the Model 100
Terminal Board in order to maintain area classification.
8. Re-connect the sensor connector to the terminal board and all other connections removed in Step 4.
DM-100 Instruction ManualRev. 3.3Page 21 of 40
9. Reconnect the power connector to the terminal board.
10. Re-install the DM-100 Display, if one was installed.
11. Reinstall the junction box cover, and restore power to the sensor.
If the ITM detects any functional errors the ITM will bring the mA output to 0mA and hold it there until the
problem has been resolved. If the unit has a Display, the display will show an error code. Error codes are
displayed as FLXX where XX is the actual error code.
AutoSpan Fault (FL01)
This fault occurs when a span calibration has not been performed in the last 180 days. Execute a span
calibration to clear this fault.
Transmitter Not Responding (FL05, FL06)
Verify condulet has no accumulated water or abnormal corrosion.
Verify required DC power is applied to correct terminals. Swap with a known-good ITM to determine
if ITM is faulty.
Clearing Problem (FL07)
The sensor must recover to < 10% of range in < 5 min after Span calibration is complete. Verify the
cal gas is being removed at the appropriate time during span calibration.
Background gas may be present. Use bottled air (zero air or N2) if there is a known continuous
background level.
Check validity of span gas using pull tube or other means (check MFG date on cal gas cylinder).
Use proper cal gas regulators and tubing for highly corrosive gases.
Check for obstructions affecting cal gas hitting sensor face, including being wet, blocked, or corroded.
H2S sensors assemblies use 100 Series Bottom Housing Assembly with integral filter. Clean or replace
if necessary.
Replace the plug-in toxic sensor.
Stability Fault (FL08)
Verify the cal gas cylinder is not close to being empty.
Check validity of span gas using pull tube or other means, verify MFG date on cal gas cylinder. Use
proper cal gas regulators and tubing for highly corrosive gases.
If using Splashguard with Integral Cal Port, must use Calibration Wind Guard or air movement can
compromise span gas delivery
Check for obstructions affecting cal gas hitting sensor face, including being wet, blocked, or corroded.
H2S sensors assemblies use 100 Series Bottom Housing Assembly with integral filter. Clean or replace
if necessary.
Replace the plug-in toxic sensor.
DM-100 Instruction ManualRev. 3.3Page 23 of 40
Model DM-100
Range Fault (FL09)
Check validity of span gas with regulator and sample tubing in place using pull tube or other means
(check MFG date on cal gas cylinder). Use proper cal gas regulators and tubing for highly corrosive
gases (HF, HCI, Cl2, NH3, HBR, F2, etc.)
Check for obstructions affecting cal gas hitting sensor face (including being wet, blocked, or
corroded). H2S sensors assemblies use DM-100 Bottom Housing Assembly with integral filter. Clean
or replace if necessary.
If using Splashguard with Integral Cal Port, must use Calibration Wind Guard or air movement can
compromise span gas delivery
Verify there is no background cross interference gases.
Replace the plug-in toxic sensor.
Sensor Fault (FL10)
Verify that the sensor cell is plugged into the ITM.
Swap cell with a known good cell to see if the fault clears.
Replace the sensor cell.
Zero Fault (FL11)
The sensor zero baseline may have drifted lower. Perform Zero Calibration. Use Zero Air or N2source
(Section 3.3.1, Zero Calibration). Allow more time for zero stabilization if usuing a biased sensor type.
Verify that the field wiring is properly shielded and grounded.
Verify that the power source is stable.
Contact Detcon to optimize shielding and grounding.
Add Detcon’s RFI Protection Circuit Accessory (PN 975-343002-007) if problem is proven RFI induced.
Nuisance Alarms
Check condulet for accumulated water and abnormal corrosion on terminal board. If nuisance alarms
are happening at night, suspect condensation in condulet.
Add or replace Detcon’s Condensation Prevention Packet (PN 960-202200-000).
Investigate the presence of other target gases that are causing cross-interference signals.
Determine if cause is RFI induced.
Unreadable Display (If a DM-100 display is installed.)
If due to excessive sunlight, install a sunshade to reduce glare.
Replace Display Assembly.
Replace DM-100 Display.
Blank or Incorrect Reading on Display (If a DM-100 display is installed.)
ITM has an internal fault, problem with display.
Swap with a known-good ITM to determine if ITM is faulty.
DM-100 Instruction ManualRev. 3.3Page 24 of 40
Model DM-100
Swap DM-100 Display Terminal Board with known good board.
Swap DM-100 Display with known good display.
5.1Smart Display Error Codes
These error codes are determined by the smart display and must be rectified before normal operation of the
unit will continue.
ER01
Firmware Incompatible: Sensor firmware version is not compatible with the display.
ER02
Zero Range: The sensor has a range value of zero.
ER03
Zero Auto Span: The sensor has an Auto Span value of zero.
All Technical Service and Repair activities should be handled by the Detcon Service Department via phone,
fax or email (contact information given above). RMA numbers should be obtained from the Detcon Service
Department prior to equipment being returned. For on-line technical service, have the model number, part
number, and serial number of product(s) in question available.
All Sales activities (including spare parts purchase) should be handled by the Detcon Sales Department via
phone, fax or email (contact information given above).
Warranty Notice
Detcon Inc. warrants the Model DM-100 gas sensor to be free from defects in workmanship of material under
normal use and service for two years from the date of shipment on the transmitter electronics. See Warranty
details in Section 7 DM-100 Sensor Warranty.
Detcon Inc. will repair or replace without charge any such equipment found to be defective during the
warranty period. Full determination of the nature of, and responsibility for, defective or damaged equipment
will be made by Detcon Inc. personnel.
Defective or damaged equipment must be shipped to the Detcon Inc. factory or representative from which the
original shipment was made. In all cases, this warranty is limited to the cost of the equipment supplied by
Detcon Inc. The customer will assume all liability for the misuse of this equipment by its employees or other
contracted personnel.
All warranties are contingent upon the proper use in the application for which the product was intended and
does not cover products which have been modified or repaired without Detcon Inc. approval, or which have
been subjected to neglect, accident, improper installation or application, or on which the original identification
marks have been removed or altered.
Except for the express warranty stated above, Detcon Inc. disclaims all warranties with regard to the products
sold. Including all implied warranties of merchantability and fitness and the express warranties stated herein
are in lieu of all obligations or liabilities on the part of Detcon Inc. for damages including, but not limited to,
consequential damages arising out of, or in connection with, the performance of the product.
DM-100 Instruction ManualRev. 3.3Page 26 of 40
Model DM-100
7.DM-100 Sensor Warranty
Plug-in Sensor Warranty
Detcon Inc. warrants, under normal intended use, each new intelligent plug-in sensor per the period specified
in the Warranty column of Table 3, Sensor Specific Data (Section 8.2, Sensor Specific Data) and under the
conditions described as follows:
The warranty period begins on the date of shipment to the original purchaser.
The sensor element is warranted to be free of defects in material and workmanship.
Should any sensor fail to perform in accordance with published specifications within the warranty
period, return the defective part to Detcon, Inc., 4055 Technology Forest Blvd, The Woodlands, Texas
77381, for necessary repairs or replacement.
Terms & Conditions
The original serial number must be legible on each sensor element base.
Shipping point is FOB the Detcon factory.
Net payment is due within 30 days of invoice.
Detcon, Inc. reserves the right to refund the original purchase price in lieu of sensor replacement.
ITM Electronics Warranty
Detcon Inc. warrants, under intended normal use, each new Model 100 ITM to be free from defects in material
and workmanship for a period of two years from the date of shipment to the original purchaser. All warranties
and service policies are FOB the Detcon facility located in The Woodlands, Texas.
Terms & Conditions
The original serial number must be legible on each ITM.
Shipping point is FOB the Detcon factory.
Net payment is due within 30 days of invoice.
Detcon, Inc. reserves the right to refund the original purchase price in lieu of ITM replacement.
DM-100 Instruction ManualRev. 3.3Page 27 of 40
8.Appendix
8.1Specifications
System Specifications
Sensor Type:Continuous diffusion/adsorption type
3-Electrode Electrochemical Sensor (2-Electrode for O2)
Plug-in Replaceable Type
Sensor Life:2 years typical
Measuring Ranges:0-1ppm up to 0-10,000ppm (Toxic Gases)
0-1% up to 0-25% volume (O2)
Accuracy/ Repeatability:±2% of full-range (other Toxic Gases)
±1% of full-range (O2)
Response Time:T90 < 30 seconds typical (Table 3)
Electrical Classification:CSA and US (NRTL)
Class I, Division 1, Groups A, B, C, D
Model DM-100
ATEX
Class I, Zone 1, Group IIC
Ex d [ib] ib IIC T6
Approvals:
Warranty:Electronics – 2 years
Environmental Specifications
Operating Temperature:-40°C to +50°C typical (Table 3)
Storage Temperature:-35°C to +55°C typical
Operating Humidity:10-95% RH Continuous Duty (Table 3)
Operating Pressure:Ambient ± 10%
Air Velocity:0-5 meters/second
Electrical Specifications
Input Voltage:10-28 VDC
CSAUS, ATEX, CE Marking
C
Sensor – (Table 3)
0-100% RH Short-Term Duration Only
Power Consumption:Normal operation = 4 mA (0.1 watts @ 24VDC);
Maximum = 20 mA (0.5 watts @ 24VDC; 0.23 watts @ 11.5VDC)
371-12EB00-100
371-444400-100T90=30<5%signal loss/year -40 to+5015 to 903 years
371-12EO00-100
371-24EZ00-100
1
Time
(seconds)
T90<140<5%signal loss/year -20 to+5015 to 902 years
T90<140<5%signal loss/year -20 to+5015 to 902 years
T90<140<5%signal loss/year -20 to+5015 to 902 years
T90<140<5%signal loss/year -20 to+5015 to 902 years
T90<140<5%signal loss/year -20 to+5015 to 902 years
T90<45
SpanDrift
<2%signal
loss/month
<5%signal
loss/month
<2%signal
loss/month
<2%signal
loss/month
<2%signal
loss/month
<1%signal
loss/month
<5%signal
loss/month
<2%signal
loss/month
Temperatur
e Range °C
-20 to+5015 to 902 years
-20 to+4020 to 95 1.5 years
-20 to+5015 to 902 years
-20 to+5015 to 902 years
-20 to+5015 to 902 years
-20 to+4010 to 952 years
-20 to+4020 to 95 1.5 years
-40 to+5015 to 902 years
Humidity
Range%
Warranty
1
The last three digits of the Part Number are the range of the sensor cell. I.E. "-100" is a 100ppm range.
DM-100 Instruction ManualRev. 3.3Page 29 of 40
Model DM-100
Response
C2H
4
C2H4O
F
2
CH2O
1.5 years
1.5 years
CH3OH
ears
1.5 years
1.5 years
C4H6O
2
C2H3Cl
GasGasNamePart Number
Ethylene
Ethylene Oxide
371-12ED00-100
371-12EJ00-100
Fluorine371-272700-001T90<80<5%signal loss/year -10 to+4010 to 95 1.5 years
T90<140<5%signal loss/year -20 to+5015 to 902 years
T90<140<5%signal loss/year -20 to+5015 to 902 years
T90<140<5%signal loss/year -20 to+5015 to 902 years
T90<60
T90<70
<1%signal
loss/month
<5%signal
loss/month
<2%signal
loss/month
<2%signal
loss/month
<3%signal
loss/month
<2%signal
loss/month
<5%signal
loss/month
<10%signal
loss/month
<2%signal
loss/month
-20 to+4020 to 95 1.5 years
-10 to+4010 to 951 year
-20 to+5015 to 902 years
-40 to+405 to 952 years
-20 to+4010 to 95
-20 to+4010 to 95
-40 to+405 to 952 years
-20 to+3510 to 80 1.5 years
-40 to+5015 to 902 years
T90<140<5%signal loss/year -20 to+5015 to 902 years
T90<45
<2%signal
loss/month
<2%signal
loss/month
<2%signal
loss/month
<1%signal
loss/month
<1%signal
loss/month
<1%signal
loss/month
<1%signal
loss/month
<2%signal
loss/month
-40 to+5015 to 902 years
-20 to+5015 to 903 years
-20 to+5015 to 902 years
-10 to+4010 to 952 years
-20 to+4010 to 95 1.5 y
-20 to+4020 to 95
-20 to+4020 to 95
-20 to+5015 to 902 years
T90<140<5%signal loss/year -20 to+5015 to 902 years
T90<140<5%signal loss/year -20 to+5015 to 902 years
Warranty
DM-100 Instruction ManualRev. 3.3Page 30 of 40
Model DM-100
Acetyldehyde
Dimethyl Sulfide
Methane
4
Acetylene
2
Disilane
6
Methanol
Acrylonitrile
Epichlorohydrin
ketone
Alcohols
Ethanol
Methyl Mercaptan
Amines
Ethyl Mercaptan
Nitric Oxide
Ammonia
3
Ethylene
4
Nitrogen
2
Arsenic Triflouride
3
Ethylene Oxide
Nitrogen Dioxide
2
Arsenic Pentaflouride
5
Fluorine
2
Ozone
3
Arsine
3
Formaldehyde
Phosgene
2
Boron Triflouride
3
Germane
4
Phosphine
3
Bromine
2
Hydrazine
4
3
Butadiene
6
Hydrocarbons
4
Hydrocarbons (unsaturated)
Silicon
2
Hydrogen
2
Silicon Tetra Fluoride
4
Carbon Disulfide
2
Hydrogen Bromide
Sulfur Dioxide
2
Carbon Oxide Sulfide
Hydrogen Chloride
Tetrahydrothiophene
Carbon Monoxide
Cyanide
Thiophane
Carbonyl Sulfide
Hydrogen Fluoride
Toluene
3
Chlorine
2
Hydrogen Selenide
Tungsten Hexafluoride
6
Chlorine Dioxide
2
Hydrogen Sulfide
Vinyl Acetate
2
Chlorine Trifluoride
3
thyl Sulfide
Vinyl Chloride
Diborane
6
Disilane
7
8.3 Interference Table
To match the interfering gas symbol with the gas name, reference Table 4, Interfering Gases. Then refer to
Table 5, Cross Interference Table which extends for five pages with each sensor specific gas repeated in each
section of the table, for a column listing of 40 gases. The list is followed by a row of 14 possible interfering
gases per page. Review each page for the applicable sensor gas and then scan across the row for possible
interference gases.
8.4 Proper Application and Maintenance of Acrylonitrile Sensor
Acrylonitrile (ACN) is a very dangerous toxic gas that has OSHA and NIOSH TWA limits of 1 and 2 ppm
respectively. It has an IDLH (Immediately Dangerous to Life and Health) limit of 85 ppm and a 15 minute
ceiling limit exposure of 10 ppm.
The Detcon Model DM-700 Acrylonitrile Sensor is based on an electrochemical sensor which has certain
limitations of use. Although it has good original span sensitivity to measure acrylonitrile, it has been known in
certain application cases to lose sensitivity over time.
Continuous exposure to background ACN levels or repeated high ACN exposures will cause the sensor’s
response to ACN gas to be lost, and hence its useful life be shortened.
It is not reliably suitable for strict industrial hygiene monitoring where the application goal may be to assure
that the ACN levels remain below the 2 ppm TWA limits.
When properly maintained it does offer the ability to function as gross leak detection method for ACN
releases.
The lowest recommended scale range for ACN is 0- 50 ppm. The lowest recommended alarm set limit is 4
ppm.
Sensor Warranty is 6 months (this shortened warranty period reflects the vulnerability to unpredictable losses
of sensitivity).
Using appropriate PPE, the sensor should periodically be span calibrated with ACN target gas (or occasionally
bump tested with ACN target gas). However, frequent exposures to ACN during calibrations and bump testing
will also shorten the life of the sensor. To address this, it is possible to use Carbon Monoxide (CO) as a crosscalibration gas, but CO may only be used if it is in combination with a program of periodic ACN bump testing
that confirms the ultimate ability to adequately sense the ACN should a release occur. If the ACN bump test
result is not acceptable, then a formal ACN span calibration must take place.
The end-user should work with Detcon to assure that a suitable amount of replacement Plug-in sensors are
available on hand to handle the ongoing exchange of sensors that may require periodic replacement.
DM-100 Instruction ManualRev. 3.3Page 37 of 40
8.5 Intrinsically Safe Installation Guidelines, Control Drawing #3993
Replacement Plug-in toxic gas sensor (Table 3, Sensor Specific Data)
adapter, O-Ring and Gasket)
(Used in H2S sensor assemblies) (includes DM 100 Splash Guard adapter,
O-Ring ,Gasket and Filter)
Model DM-100
943-000000-000Calibration Wind Guard
943-000006-132Threaded Calibration Adapter
943-000000-000Calibration Wind Guard
943-01747-T05Calibration Adapter for highly reactive gases
943-050000-132Span Gas Kit: Includes calibration adapter, span gas humidifier, 500cc/min
fixed flow regulator, and carrying case. (Not including gas).
943-050000-HRGHighly Reactive Gas Span Gas Kit (Used for NH3, Cl2, HCl, HBr, etc.)
See DetconSpan Gases – various
943-05AM00-000500 cc/min Fixed Flow Regulator for span gas bottle
0.111/08/2010Update to Cross Interference table to correct wrong value for
C2H3CL against CO. Previous value was 1250=100, corrected
value is 200=100
0.211/17/2010Added updated table for Jumper descriptions and Jumper
settings on DM-100 Terminal Board
0.311/30/2010Corrections to Cross Interference Table, and some spellingLU
1.002/02/2011Revised ATEX operational guidelines. Updated manual to
reflect most current template. Made significant changes due to
creation of Wireless DM-100 manual so manuals can
complement each other. This includes removing duplicate
tables and figures, adding/modifying tables and figures,
updating drawings, adding/modifying sections, etc.
1.102/15/2011Added additional notes required by approval agencies.LU
1.204/06/2011Added references to 100 Series Bottom Housing Assembly with
integral filter. Added 100 Series Bottom Housing Assembly
with integral filter to spare parts. Modified troubleshooting
section to reference use of 100 Series Bottom Housing
Assembly with integral filter
1.304/13/2011Add additional guidelines in 2.1 per ATEX requirements.VR
1.406/02/2011Added “DM-200L Toxic Gas Sensors” on Cover SheetLU
1.508/01/2011Added DM-100 intrinsically safe installation notes drawing to
back of manual.
2.008/17/2011Updated Terminal Boards, new displayLU
3.010/5/2012Added AutoZero and AutoSpanLU
3.111/22/13Corrected instructions for performing span with no displayLU
3.212/26/13Added Wind Guard to Calibration ProcedureBM
3.301/30/14Stress and highlight parts of span calibration for O2 sensorsBM
LU
LU
BM
BM
LU
Shipping Address: 4055 Technology Forest Blvd, The Woodlands, Texas 77381
Mailing Address: P.O. Box 8067, The Woodlands Texas 77387-8067