ENMET ISA-44-RAL-OD - Manual (Page 18)

ENMET Corporation ISA-44RAL-OD / ISA-44RAH-OD
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6. Turn operation switch to H ORN O FF . Open the regulator on the top of the high-level calibration gas cylinder. This
brings the gas into the sampling assembly.
7. Regulate the flow of calibration gas according to the "...SET" mark or between 7 – 12 PSI on the pressure regulator
dial.
8. Let the high-level calibration gas flow into the system for 5 minutes. This assures a full and balanced response from
the sensor. During this time, the meter should have risen above the low-level alarm point and the amber light should
have gone on.
9. With the gas still flowing, adjust the Meter Adjust Potentiometer with a small screwdriver (adjust this pot CCW to
increase, CW to decrease meter reading). You want to have the same meter reading as the calibration gas
concentration. This sets the alarm point. Refer to Figure 2.
Note: Do not adjust for instantaneous alarm when test gas is first released. If you do, the calibration will be
inaccurate, and the sensor will be overly sensitive.
10. Adjust the High Level Alarm Set Adjust Potentiometer CCW until the red alarm light is just barely triggered. At this
point, verify the audio alarm is operational by turning the operation switch to O PERATE momentarily.
N OTE : If red alarm light is on prior to the potentiometer adjustment, adjust this pot. cw until the light deactivates,
then readjust
CCW until the light just barely activates.
11. Shut off the calibration gas flow (at the regulator on the gas cylinder).
12. Allow pressure to equalize – wait until the pressure meter on the humidifier-regulator assembly reads zero. Remove
calibration fixture, and reconnect humidifier-regulator assembly to compressed air line. Allow air to flow over
sensor for 10 minutes to clear the sensor.
13. In a similar manner, apply the low level calibration gas for five minutes
14. While the gas is still flowing, adjust the Low Alarm Set Adjust potentiometer CCW until the amber alarm light just
activates.
N OTE : If amber light is on prior to pot. adjustment, adjust this pot. CW until light is off, then readjust CCW until light just
activates.
I MPORTANT : The meter may not display the exact low level alarm.
D O N OT change the low level alarm meter reading unless grossly off (four meter needle widths or more). If far off,
recalibrate the high alarm, meter reading (step 9).
15. Repeat step 11.
16. Repeat step 12.
17. Reconnect the sample head to the air line.
18. The flow of clean air should clear the unit from its gas alarm state within 3-5 minutes. After 5 minutes, turn the
operation switch to O PERATE .
19. Clean compressed air lines will show a meter reading from 0 – 1/3 full scale. Green power light will indicate a clean
condition.
20. Carbon Monoxide Detection Channel Calibration is complete.
Verify the operation switch is in the O PERATE position.