Dräger PIR 3000, Инструкция по эксплуатации

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17
Operational Characteristics
Checking the Signal Transmission, Checking the Alarm Trigger and Display-
ing the Gas Category
The gas transmitter can create an output signal of 80 % of the full scale value, even
without exposure to test gas. This 80% signal can be used to
— check the signal transmission of the central device,
— match central device and sensor signal,
— check the alarm triggering of the gas warning system.
After issuing the 80% signal, the gas category set at the gas transmitter is
displayed before the gas transmitter returns to normal operation.
 De-energising the alarm activation of the central device (not during alarm
testing).
 Expose the gas transmitter to nitrogen, synthetic air, and/or fresh air via
calibration adapter and wait until measurement value stabilises.
 Place the magnetic pin onto the transmitter surface area marked by the " "
icon and hold it there (within the black frame) for at least 5 seconds. After five
seconds, the output signal of the gas transmitter changes to 3 mA (span gas
signal) and remains there for as long as the magnetic pin is held against it. At the
same time, a zerosetting of the optical measuring unit is carried out
automatically.
 Remove the magnetic pin. After 30 seconds, the device exits the automatic
zerosetting routine. As confirmation of the automatic zerosetting, the output
signal changes back to the span gas signal (3 mA). This signal is indicated for
the same period of time as when starting the automatic zerosetting routine. After
that, the output signal of the gas transmitter changes to 4 mA (0 % signal).
 Check the display of the central device: set point 0 %LEL.
 If required, manually set the zero point at the gas transmitter to a display of
0 %LEL.
 Place the magnetic pin onto the transmitter surface area marked by the " "
icon (within the black frame) and hold it there. After ten seconds, the output
signal of the gas transmitter changes to 16.8 mA (80% signal) and remains there
for as long as the magnetic pin is held against it.
 Check the display of the central device: set point 80 %LEL.
 If required, adjust the span at the central device until the central device displays
80 %LEL. While doing so, observe the information in the operating manual of the
central device pertaining to this subject.
 Remove the magnetic pin. The gas transmitter changes to an output signal
which displays the currently set gas category according to the following table:
Gas category mA Display [%LEL]
methane 7.2 20
propane 10.4 40
ethylene 13.6 60
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