ENMET ISA-RAL-M - Manual (Page 11)

ISA-RAL-M, ISA-RAH-M ENMET Corporation
7
5.0 Initial 5.0 Initial Warm-Up and Operation Warm-Up and Operation
The ISA-RAL-M incorporates a Metallic Oxide Semiconductor (MOS) sensor to detect carbon monoxide. During
periods of inactivity, contaminants may build up on the sensor element that need to be cleaned off. It is normal for the
instrument to go into an alarm condition when first powered up after a time of storage or after power has been
disconnected for some time.
C AUTION : Do NOT operate the ISA-RAL-M without air passing over the sensor. The absence of air flow over
the sensor when the instrument is in operation can permanently damage the sensor!!!
You need a voltmeter for this procedure.
1. Mount and install the ISA-RAL-M as outlined in section 4.0.
N OTE : This unit has no ON/OFF switch for the power; this safety monitoring device is designed to operate
continuously. Turn the Operation Switch to HORN OFF to silence the audio alarm during warm-up.
2. Turn the operation switch to PURGE ON. The alarm light will go on; don't worry, this is normal.
3. Open the control unit. With a voltmeter, check the voltage across terminals 6 and 7 on TB1 (terminal 6 is positive,
terminal 7 is negative). The voltage must be 1.60 Vdc within a 0.07 Vdc range. This voltage is not adjustable, if it
is not within this range, contact your local distributor.
4. Let clean air pass over the sensor for at least one hour to purge (clear) the sensor of contaminants. CLEAN AIR
MUST PASS OVER THE SENSOR. If you suspect contaminated air (or really dirty conditions) in your
compressor, use bottled clean air. Do not operate the unit without air passing over the sensor. If you do, you are
likely to contaminate the sensor.
N OTE : After long periods of storage (several days or more ), extend the purge operation to several hours; or operation
switch may be left set to PURGE ON overnight.
5. Purging is complete when the red alarm light goes out, and the meter stabilizes at a low reading.
6. Turn the operation switch to HORN OFF. Some meter drift is normal. Open the control unit and measure the
voltage across terminals 6 and 7 of TB1 (terminal 6 is positive, terminal 7 is negative). The voltage must be 0.86
Vdc within a 0.07 Vdc range. This voltage is not adjustable, if it is not within this range, contact your local
distributor.
7. Turn the operation switch to OPERATE .
Reference: State of Operation of ISA-RAL-M, ISA-RAH-M
No alarms. Green light is off.
Green light is on. Amber light or red light/audio alarm on.
Normal Operation:
Enclosure feels warm to the touch.
Alarm State:
Relay contacts in alarm position.
If pressure is applied to the regulator input, and air is not bubbling through the humidifier, check to see that the
regulator is adjusted to between 7 and 12
PSI . If this is not the problem, then the metering orifice is probably plugged;
you must replace it. See section 7.1 for part number.
Important: When replacing the orifice, use teflon thread to seal the connections.
Do Not use joint sealing compound.