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Rev. 2.1 7-7-2017
Copyright © 2017 by Cool Air Incorporated. All rights reserved.
For the LBW-420-LEL, the maximum allowable resistance in the
receiving device must not exceed Rmax using this formula:
Rmax = 50 (Vs – 7.5)
Where Vs is the supply voltage in volts DC for the 4-20 mA circuit.
For example, with a supply voltage of 24 VDC, the maximum
allowable resistance is 825 Ω.
INSTALLATION AND SETUP
Caution: Do not apply power to the detector until instructed to
do so.
The detector comes with four mounting feet, packaged in the
detector enclosure for shipment. Use the directions that accompany
the mounting feet for mounting the detector enclosure.
The detector should be mounted in a location where ammonia leaks
are most likely to occur, such as near valve groups, compressors,
and refrigeration coils. Be sure the detector is visible and easily
accessible. Avoid locating the detector where it might be damaged
during wash-down.
When power is applied to the detector, it will immediately go into
alarm status and the display will show an unusually large ammonia
concentration. This is normal. When the sensor warms to normal
operating temperature (usually about a minute) the detector will
return to a non-alarm status. However, you will
need reset the relays
(see “
Resetting the Relays”
) as they are latched in the alarm
condition until a manual reset is initiated.
For this reason, the
detector should be placed in service mode before applying
power to the detector to avoid unwanted alarm condition.
