Foxcroft FX-Mini, Руководство по эксплуатации

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Calibration
Sensor Response (Bump) Test
Important
The sensor response test, also known as a “bump” test, is only used to test the gas sensor’s ability to
respond to a gas leak. This test is not a calibration. Sensor response, or bump tests should only be
done with a known target concentration gas.
Note that the Industrial Safety Equipment Association (ISEA) defines a bump test as follows:
Functional (bump) test – A means of verifying calibration by using a known concentration of test gas to
demonstrate that an instrument’s response to the test gas is within acceptable limits.
It is
very important that this test sets off all the alarms and that the target concentration gas level
corresponds to the maximum millivolt output at full gas range.
Full calibration is required if the test fails to set off alarms and the target concentration gas level does
not corresponds to the maximum millivolt output at full gas range.
1. Toxic gas sensors must have had a recent accurate zero point setting.
2. Install the calibration nose into the sensor opening/collar; be sure the nose is seated and the sealing
caps are removed.
3. Connect the target calibration gas sample tubing to the nose. Oxygen sensors require a mixture of
16% Oxygen with the balance in Nitrogen.
4. Apply target calibration gas with a known concentration using a fixed feed rate gas regulator with
C10 connection dedicated to the target gas. The required fixed feed rate for toxic gases is 1 liter per
min (LPM); Oxygen sensors require a 0.5 LPM fixed flow rate. The sensor should begin to alarm within
20 seconds.
5. Wait for a stable reading to be obtained and compare it to the concentration on the calibration gas
cylinder. The known target gas concentration level should be indicated on the LED display and all the
alarms should be set off including the buzzer.
7. If the target calibration gas level is indicated on the multi-meter and the alarms are set off including
the buzzer, the test is complete.
8. Remove calibration nose, the detector should return to zero in a few minutes. Reset danger alarm.
9. If the target calibration gas level fails to set off all alarms a full calibration is required.