Det-Tronics GTS Sensor Module SAFETY MANUAL - Manual (Page 4)

1.1 95-8685 4
oPERATIoN, MAINTENANCE, INSPECTIoN AND
PRooF TESTING
All normal installation and field calibration
recommendations as documented in the GT3000
instruction manual are applicable to the Safety Certified
GT3000 Toxic Gas Detector.
Safety-Certified GT3000 gas detectors require Proof
testing to be performed in all cases.
Personnel performing Proof Test procedures shall be
competent to perform the task. All proof test results
must be recorded and analyzed. Any corrective actions
taken must be documented in the event that an error is
found in the safety functionality. The Proof tests must be
performed at a frequency as shown in Table 1.
WARNING
Failure to perform the specified testing and
inspection may lower or void the SIL rating for the
product or system.
VISUAL FIELD INSPECTIoN PRooF TEST
Tools Required: None
Visual inspection of all Safety-Certified GT3000 gas
detectors shall be conducted as needed to confirm
that no external blockage of gas/vapor path into the
sensing chamber exists, eg. debris, trash, snow,
mud, external equipment, etc. Corrective action
shall include removal of such impediments should
they exist. All gas detectors must be inspected to
ensure that they are capable of providing expected
performance and protection.
Completion of Visual Field Inspection Proof test must
be recorded and documented in the SIS logbook.
RESPoNSE PRooF TEST
Tools Required: Compressed Calibration Gas Kit
provided by Det-Tronics
This proof test, commonly referred to as a “gas
bump test”, requires application of high accuracy
compressed calibration gas to the detector while in
NORMAL operational mode and inspecting the signal
output level to ensure that the signal output is accurately
indicative of the applied test gas concentration.
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!
Proof Test Sequence
1. Inhibit alarm and fault response at the control
device.
2. Apply calibration test gas to the sensor.
3. Verify correct change of state at the control device
for the GT3000 4-20 mA output. Criteria for the
4-20 mA inspection pass is a response signal within
±10% for H
2
S and ±0.5% V/V for O
2
of applied
gas concentration (generally, a 50% full scale test
concentration is applied).
4. Remove the test gas and ensure that the unit returns
to normal operation.
5. Re-activate alarm and fault response at the control
device.
If response test is not within acceptable limits or fails
for any reason, a Full Calibration procedure must be
performed and the Proof Test re-performed.
GT3000 Proof Test Name Commissioning Frequency
Visual Field Inspection Proof Test Yes
As needed, depending on level and type of
contaminants present
Response Proof Test Yes 1 year
Table 1—Frequency for Performing Proof Tests