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Model S4000T
20
Default settings for Channel 2 are: address 2, 19.2 kbaud, 8-N-1.
NOTE –
The address can be adjusted from 1 - 247. Channel 1 and Channel 2
addresses may be the same.
4.5 Gas Check Mode
The sensor’s response can be checked without activating external alarms by placing
the Model S4000T in Gas Check Mode. In this Mode, the alarm relays are inhibited
and the analog output is fixed at 1.5mA.
4.5.1 Procedure for Checking the Calibration:
Place the magnet over the GM Logo on the cover of the Model S4000T. Remove the
magnet when a flashing pair of bars, “
- -
” (Figure 26), appear on the display (about
ten seconds). Apply the test gas to the sensor, and the value of the gas
concentration will be indicated by the flashing display and should stabilize in one to
two minutes.
Figure 26 Gas Check
When the reading has stabilized and the test is complete, remove the gas and the
unit will return to normal operation, when the concentration drops below 5% full-
scale. If, after the reading has stabilized the sensor is to be calibrated, simply apply
the magnet to the GM Logo on the housing cover, and the unit will enter Calibration
Mode.
Gas Check Mode can be aborted if gas has not been applied to the sensor. Simply
reapply the magnet to the GM Logo on the cover and the unit will return to normal
operation.
NOTE -
The test gas concentration must be at least 10% full-scale before the unit will
complete the Gas Check sequence. If the Model S4000T is placed in the Gas Check
mode and no gas is applied for twelve minutes, the unit will revert to a Fault
condition. Re-applying the magnet over the GM Logo will return the unit to normal
operation.