Warning – Detcon DM-700 SIL 2 Safety Manual User Manual

Page 5

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Warning:

Any external alarm equipment, systems or signaling devices that could be automatically initiated by

performing this test must be disabled or bypassed before performing this test!

When test gas is flowing into the detector, inspection of proper analog signal level output can be made by reading the
analog signal output displayed on the control device. The criteria used for inspection pass is a stabilized response signal
within +/- 20% of the applied gas level. If response test is not within acceptable limits, then a Full Calibration procedure
must be performed and the Gas Response Proof Test re-performed.

13.1 FULL CALIBRATION

Tools Required:

Zero Gas Cylinder – Zero Air or N2 (may use local ambient air if it’s confirmed to be free of the target
gas or any gases with cross-interference)

Span Calibration Gas Cylinder - 50% of FS Range Span Calibration Gas Cylinder containing target gas in
balance Air or N2 (concentration should be at least between 10% and 90% of FS Range)

Calibration Kit provided by Detcon

Programming magnet

Full Calibration shall be conducted when required. The procedure for performing the Full Calibration is
in the Calibration section of the DM-700 instruction manual. In all cases the model DM-700 gas detector
should be allowed to warm up for 5 minutes before conducting a Full Calibration.

Warning:

The 4-20mA output from the DM-700 will drop to 2mA during the Full Calibration

Successful completion of the Gas Response Proof Test must be recorded and documented in the SIS
logbook. If the Full Calibration is performed, it should also be documented in the SIS logbook.

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OUTPUT RESPONSE PROOF TEST

Tools Required:

Span Calibration Gas Cylinder - 50% of FS Range Span Calibration Gas Cylinder containing target gas in
balance Air or N2 (concentration should be at least between 10% and 90% of FS Range)

Calibration Kit provided by Detcon

The Output Proof Test is performed as follows:

1. Inhibit alarm response at the control device.
2. Apply test gas (50% of FS Range) to the detector. Verify correct 4-20mA output signal at the control device.
3. Re-activate alarm response at the control device.

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FAULT/FAILURE ACTION PLAN

In the event that a Full Calibration does not result in acceptable Gas Response Proof test, then the standard Maintenance,
Troubleshooting, and Device Repair and Return Procedures are listed in the DM-700 instruction manual must be
followed. Any failure to successfully complete the Gas Response Proof Test must be recorded and documented in the SIS
logbook.

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