AMC 210 Series User manual

210 Series
Transmitter with External
Electrochemical Sensor
INSTRUCTIONS
Installation and Operation of the
AMC-210 Series Transmitter with
External Electrochemical Sensor
IMPORTANT:
Please read these installation and operating instructions completely
and carefully before starting.
Filename:
Manual_amc210_trx w external electrochemical sensor.doc Revised, 7/16/2004 Copyright ©, Feb. 2004, AMC
The Armstrong Monitoring Corporation
215 Colonnade Road South, Nepean, Ontario, Canada K2E 7K3
Tel: [phone] • Fax: [phone] • Canada & U.S. Toll Free: 1-800-465-5777
E-mail: [email protected] • Internet: www.armstrongmonitoring.com/gas/

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TABLE OF CONTENTS
Section Title Page
1WARRANTY.............................................................................................................3
1.1 LIABILITY...........................................................................................................3
1.2 PRODUCT RETURN .........................................................................................3
1.3 MODIFICATIONS AND SUBSTITUTIONS.........................................................3
2PRODUCT INFORMATION......................................................................................4
2.1 SENSOR/TRANSMITTER..................................................................................4
2.2 FACTORY CALIBRATION.................................................................................4
3PRODUCT DESCRIPTION ......................................................................................5
3.1 GENERAL DESCRIPTION.................................................................................5
3.1.1 SENSOR / TRANSMITTER SPECIFICATIONS......................................................5
3.2 HOUSING OPTIONS.........................................................................................6
4INSTALLATION .......................................................................................................7
4.1 LOCATION AND MOUNTING............................................................................7
4.2 CABLE SELECTION AND WIRING...................................................................8
4.2.1 TRANSMITTER TO MONITOR WIRING...............................................................10
4.2.2 INTERFACING TO COMPUTER, DATALOGGER, OR NON-AMC MONITOR....11
5OPERATION AND CALIBRATION........................................................................12
5.1 OPERATION....................................................................................................12
5.2 CALIBRATION.................................................................................................12
5.2.1 EQUIPMENT REQUIRED.....................................................................................13
5.2.2 TRANSMITTER CALIBRATION/VERIFICATION SET-UP PROCEDURE............13
5.2.3 RECALIBRATION .................................................................................................14
6PREVENTIVE MAINTENANCE..............................................................................15
6.1 GENERAL........................................................................................................15
6.2 VERIFICATION OF OPERATION....................................................................15
6.3 SENSOR REPLACEMENT..............................................................................15
7ADDENDUM (FOR OXYGEN ONLY).....................................................................17

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1WARRANTY
The AMC-210 transmitter is warranted against defects in material and workmanship for two (2)
years from the date of shipment from factory. Please check equipment specifications
following this page for sensor warranty periods. Maintenance items are not warranted.
During the warranty period, The Armstrong Monitoring Corporation will repair or replace
components that prove to be defective in the opinion of AMC. We are not liable for auxiliary
interfaced equipment, or for consequential damage. This warranty shall not apply to any
product, which has been modified in any way, which has been repaired by any other party other
than a qualified technician or authorized AMC representative, or when failure is due to misuse
or conditions of use.
1.1 LIABILITY
All AMC products must be installed and maintained according to instructions. Only qualified
personnel should install and maintain the equipment.
AMC shall have no liability arising from auxiliary interfaced equipment, for consequential
damage, or the installation and operation of this equipment. AMC shall have no liability for
labour or freight costs, or any other costs or charges in excess of the amount of the invoice for
the products.
THIS WARRANTY IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED OR IMPLIED,
AND SPECIFICALLY THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
PARTICULAR PURPOSE. THERE ARE NO WARRANTIES THAT EXTEND BEYOND THE
DESCRIPTION ON THE FACE THEREOF.
WARNING
CHECK TO ASSURE THE WORKING AREA IS FREE FROM HAZARDS DURING
INSTALLATION OR WHEN PERFORMING MAINTENANCE, AND USE PROPER
PRECAUTIONS.
1.2 PRODUCT RETURN
All products returned for warranty or service should be shipped by prepaid freight and will be
accepted only with a repair number issued by AMC. All products returned to the client will be
shipped by freight collect.
1.3 MODIFICATIONS AND SUBSTITUTIONS
Due to an ongoing development program, AMC reserves the right to substitute components and
change specifications at any time without incurring any obligations.

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2PRODUCT INFORMATION
2.1 SENSOR/TRANSMITTER
Sensor/Transmitter Unit Order Number. …………………
Transmitter Part Number..……………………………………
Transmitter Serial Number.….………………………………
Sensor Part Number..………………………………………..
Sensor Serial Number………………………………………..
Power Supply Requirement…………………………………. 12 to 30 VDC @ 20 mA
Sensor Warranty………………………………………….. ________
2.2 FACTORY CALIBRATION
Gas Type……………………………………………….…..….
Zero Gas, at 4 mA Signal…………….………………..…….
Gas Concentration at 20 mA Signal………………………..
Calibration Adapter Part Number……………………………
Note:
All Armstrong Monitoring systems must be installed and maintained according to
instructions to assure proper operation. Only qualified technicians should install and
maintain the equipment.

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3PRODUCT DESCRIPTION
3.1 GENERAL DESCRIPTION
The AMC-210 series sensor/transmitter is designed to provide continuous, reliable surveillance
of surrounding air for traces of a specific hazardous gas(es) (listed in Factory Calibration,
section 2.2). This unit provides a 4 to 20 mA, variable current signal, which is proportional to
the gas concentration detected. Each sensor/transmitter unit is factory calibrated and is ready
for field installation and operation.
3.1.1 SENSOR / TRANSMITTER SPECIFICATIONS
SENSOR TYPE: Electrochemical cell.
RESPONSE TIME: Better than % step change in seconds
DRIFT: Less than ___% of full scale per ___
SENSOR SIGNAL OUTPUT: __ Linear to the concentration of gas
OPERATING TEMPERATURE: to ºC ( to ºF)
HUMIDITY: to % RH, non-condensing.
EXPECTED SENSOR LIFE: Greater than ___year(s)
Note:
Turn off power supply before removing or replacing the transmitter or sensor.

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3.2 HOUSING OPTIONS
The AMC-210 series sensor/transmitter units are available in the housings shown in Figure 1.
The explosion proof transmitter housing is rated explosion proof for Class 1, Groups B, C and D
locations and can have a corrosion resistant finish (optional). The sensors are also available as
standard or explosion proof.
PVC HOUSING:
Rectangular PVC with cover plate held by
four screws. Not for use in combustible areas
and not weather proof.
Width: 2.9”
Height: 2.25”
Length: 6”
Hub Size: 3/4” NPT
EXPLOSION-PROOF HOUSING:
Round housings with screw-on covers.
Weatherproof and explosion proof.
BCD Housing:
Width: 3.7”
Height: 2.6”
Length: 5.25”
Hub Size: 3/4” NPT
FIGURE 1: Transmitter Housing Options.

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4INSTALLATION
4.1 LOCATION AND MOUNTING
Mount the sensor/transmitter on a solid, non-vibrating surface or structure in an area where the
local concentration of gas is unaffected by the presence of ventilation systems and away from
sources of interference gases. (see Figure 2)
Note:
Mounting arrangement of the housing depends on location and mounting surface.
Mounting hardware is not supplied.
FIGURE 2: Mounting of Sensor/Transmitter (Explosion Proof Housing)

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4.2 CABLE SELECTION AND WIRING
Connection should be made using 2-conductor, shielded cable. For best signal transmission
and maximum noise rejection, run cable through steel conduit (cable must be grounded at the
monitor or power supply). Supply voltage can be measured at the transmitter (–, +) connections
at the supply source. For basic cable selection, between the source and transmitter, use a 250-
ohm load resistance, use the following chart:
WIRE GAUGE AWG 22 20 18 16
@12VDC 1000 (305) 1500 (457) 2500 (762) 3800 (1158)MAXIMUM
DISTANCE IN
FEET (METRES) @24VDC 15000 (4573) 23000 (7010) 38000 (11582) 57000 (17373)
For applications not covered by the above chart, an example is shown below for selecting the
right cable, using the graph of Figure 3 and the following formulas
Note: Some non-AMC equipment may not have the load resistance built in.
Example:
Calculations on the graph
Maximum resistance …. MR
Load resistance ………. LR
Known data
Power supply ………………………… 17 VDC
Load resistance ……………………… 180 Ohms
Wire gauge ……………………………20 AWG
Cable length / 1 Ohm resistance ….. 43.6 ft (13.3m) typical
Formula 1 : To determine remaining safe loop resistance.
Maximum resistance 518 Ohms
Load resistance - 180 Ohms
Remaining resistance 338 Ohms
Formula 2 : To determine maximum safe cable length allowed.
Remaining resistance 338 Ohms
Cable length (for 1 Ohm) x 43.6 Feet
Maximum safe cable length 14,736 Feet
Note:
If maximum safe cable length is insufficient, increase the power supply voltage and/or
reduce the load resistance.

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FIGURE 3: Cable selection graph

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4.2.1 TRANSMITTER TO MONITOR WIRING
The transmitter output (–, +) terminals connect to the (SIG, +) terminals on a channel terminal
block of the monitor (one transmitter per channel), as shown in Figure 4. Each transmitter
MUST BE CONNECTED TO ITS CORRESPONDING CHANNEL to retain factory calibration of
the trip points.
FIGURE 4: Transmitter to monitor wiring layout.

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4.2.2 INTERFACING TO COMPUTER, DATALOGGER, OR NON-AMC MONITOR
All Armstrong sensor/transmitters can be connected to computers or data loggers through
analog-to-digital converters or to non-AMC monitors. The transmitter output (–, +) terminals
connect to a filtered 12 to 30 VDC power supply through field wiring, as shown in Figure 5.
The signal output from the transmitter is a 4 to 20 mA DC current. This signal can be measured
or recorded anywhere in the supply loop if required. Alternatively, if a voltage measurement is
needed a resistor can be connected between the transmitter negative (–) output terminal and
the power supply negative (–) or common terminal, as shown in Figure 5.
FIGURE 5: Interfacing to a computer, datalogger or non-AMC monitor.

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5OPERATION AND CALIBRATION
5.1 OPERATION
The AMC-210 series sensor/transmitter is factory calibrated for the gas listed in Product
Information (section 2) at the beginning of this manual. The sensor/transmitter should not need
re-calibration when first installed and powered up, but a test for correct operation is
recommended after a stabilization period of 10 minutes.
Following stabilization, the sensor/transmitter should be sending (in a Zero Gas environment) a
4 mA signal to the monitor or controller. However, there are a few situations where a slightly
higher or lower than normal signal may be noticed. In many facilities there can be residual
levels of the gas being detected in the air at all times. These can cause a minor response from
the sensor expressed as a rise in signal. Other causes for minor signal variations include
extremes in temperature. The application of a clean air sample will verify if the elevated signal
is from background gas or equipment error.
Although the electrochemical sensors are very selective, there are some interference gases,
which can also cause a response from the sensor. These gases are listed on the detailed
Specifications sheet pertaining to the sensor in use.
5.2 CALIBRATION
The transmitter is equipped with a remote calibration feature allowing one-man calibration at the
sensor/transmitter location. The transmitter output is measured using a plug-in type “Remote
Calibration Lead” (P/N 2900-01) designed to be adaptable to most multimeters. Zero and Span
adjustments are made at the transmitter. Recalibration is necessary when replacing the sensor.
Verification of calibration should be done at least once every 6 months. For safety reasons and
highly demanding applications, monthly verification is recommended.
Factory/on-site calibration services, customer training and/or calibration adapter are available.
Specify the sensor/transmitter Part Number & Serial Number listed in section 2.1
SENSOR/TRANSMITTER and refer to section 2.2 FACTORY CALIBRATION for Gas Type and
calibration adapter when ordering any of the above.
Caution:
- Only qualified personnel should perform the actual calibration.
- Users are advised to consult The Armstrong Monitoring Corporation as to the
calibration procedure and recommended gas concentration for the application.
For some exotic gases, calibration standards needed for field calibration are not readily
available. The Armstrong Monitoring Corporation offers the following options:
1. Pre-calibrated sensor/transmitters to replace expired units.
2. Factory installation and calibration of new sensors in returned transmitters.
3. Replacement sensors supplied with a pre-calibrated electrical output.
For all above options, please contact the factory for details.

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5.2.1 EQUIPMENT REQUIRED
•Digital multimeter with a minimum display range of 20.0 mA.
•Remote calibration lead provided with the transmitter.
•Miniature screwdriver trimmer adjustment tool.
•Calibration adapter
•Zero & Span gases and regulator (Contact factory for information)
5.2.2 TRANSMITTER CALIBRATION/VERIFICATION SET-UP PROCEDURE
Note:
When applying gas, a flow rate of 0.5 to 1 liter per minute is recommended.
As the calibration procedure may cause the monitoring equipment to give a false alarm,
appropriate precautions should be taken.
To perform the following Set-Up procedure (refer to Figure 6)
1) Remove cover from transmitter housing.
2) Plug in standard test leads fully into jacks on multimeter.
3) Switch ON multimeter and select the DC Volts range greater that 1.00 VDC.
4) Apply a Zero gas sample, or with the sensor in clean air, adjust the Zero trimmer for
a stabilized reading approaching of 0.000 VDC measured at the test points. This
measurement ideally should lie in the range of – 0.005 to 0.000 VDC.
5) Unplug test leads and connect the “Remote Calibration Lead” to the multimeter.
BLACK lead to negative or common (–)
RED lead to positive (+)
6) Select the next range greater than 20 mA DC full scale on the multimeter.
7) Insert the plug end of the “Remote Calibration Lead” fully into the CAL jack on the
transmitter.
8) Adjust the 4 mA trimmer until the multimeter reads 4.00 mA.
9) Apply a Span gas sample and adjust Span trimmer to 20 mA when full-scale gas
concentration is used.
Note: The Span gas sample need not be of the full-scale concentration but may be a
fraction of this. Since the transmitter output range is 4 to 20 mA, a full scale
concentration gas should read 20 mA after a few moments of sensor exposure.
Similarly, a half scale concentration gas should read 12 mA.

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5.2.3 RECALIBRATION
For full recalibration adjustments, follow the Set-Up procedure steps 1 to 9 inclusive. There are
two adjustments to be made for periodic recalibration: Zero and Span.
Zero: With the sensor in Zero Gas, the transmitter output signal current should read 4 mA.
This is obtained by adjusting the Zero trimmer on the transmitter for a voltage of
0.000 VDC at the test points in Figure 6. It is possible, under certain conditions that
the Zero current will fall below 4 mA.
Span: While the sensor is exposed to the calibration gas sample, adjust the Span trimmer on
the transmitter to set the transmitter output signal current proportional to the applied
gas concentration.
FIGURE 6: Calibration/Verification Set-up

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6PREVENTIVE MAINTENANCE
6.1 GENERAL
The sensor/transmitter unit should be brushed or wiped clean of any dust or dirt at least once a
year or more, depending on the rate of accumulation.
To avoid sensor damage, the unit MUST NOT be submerged in any liquids. Any hosing or
splashing of the unit with any liquids must also be avoided.
6.2 VERIFICATION OF OPERATION
To verify the operation of the sensor/transmitter unit, perform a test to ensure that it is still
responding to gas. This test should be performed every 6 months. For more demanding
applications, verification should be performed on a monthly basis.
6.3 SENSOR REPLACEMENT
Caution:
Turn off the power supply before attempting the following.
Expected sensor life is as indicated in Section 3.1.1. The signal from the sensor will be greatly
reduced when its replacement is required. The sensor should be replaced when it no longer
responds to the presence of gas or has an unstable zero signal.
When the sensor needs replacing, reorder the “Sensor Part Number” listed in the Product
Information (section 2). When sensors are shipped, some sensor leads may be shorted
together. This is done to provide rapid stabilization of the sensor signal after installation. To
wire the sensor for correct operation, first separate (cut apart) the shorted leads, if any, then
connect the RED lead to the “R” terminal, then BLACK to “S” and the YELLOW to “C” of the
sensor terminal block on the transmitter. See Figure 7 for the sensor replacement and wiring
procedure.
Note:
Allow 10 minutes for the new sensor to stabilize before recalibration, and then follow
the instructions in calibration (section 5.2) of this manual.

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FIGURE 7: Sensor replacement and wiring procedure.

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7ADDENDUM (FOR OXYGEN ONLY)
This AMC-210 Series (2-wire sensor/transmitter with external electrochemical sensor) has been
modified and the following information replaces the terminal block & sensor wiring of Figures 4,
6, and 7.
The sensor/transmitter shows that the three wires changed to two wires for OXYGEN SENSOR
ONLY. Terminal block & sensor wiring configuration are as shown below:
Figure 8: Transmitter wiring layout for oxygen only.