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3
Operation
TM
The AirScan
iR has several modes of operation,
including two normal run modes, two 4/20 mA loop
check modes and five calibration modes. These will
be explained in Operation, Section C, Modes of
Operation. Modes are entered by properly activating
pushbuttons located on the circuit board, shown in
Figure 4.
Sensor operation status is indicated by the blink
pattern of seven LED's located in a vertical row on the
right side of the sensor circuit board (see Figure 4).
LED status is differentiated by color and duration/
pattern of blink(s). LED Indicators and Blink
Sequences are shown in Figure 6, followed by an
explanation of blink patterns.
Start-Up Procedure
A
Before applying power, make a final check of all wiring
for continuity, shorts, grounds, etc. It is usually best to
disconnect external alarms and other equipment from
the sensor until the initial start-up procedures are
completed.
Check the power supply voltage to the sensor with a
digital volt meter set to VDC. Place the black lead on
sensor terminal GND and the red lead on +24 (see
Figure 4, Note 1). Voltage should be between 21 and
28 VDC. If voltage is outside this range, check power
supply and wiring.
After power-up, ensure the LED's below are
operational as follows (see Figure 3):
•
Green "Power" LED continuous ON
•
Both Fault LED's are OFF
•
Green "source" LED is blinking once every
2 seconds
NOTE: For cold/humid adverse environmental
conditions the "ATMOS" LED may be turning on and
off periodically. In addition, the "system" LED may be
blinking or continuous ON, also described in later
sections.
Manning AirScan-iR Refrigerant Sensor
19100 AirScan-iR-ind 05/2006 REVA Copyright © 2006 Manning Systems, Inc. All Rights Reserved.
IMPORTANT: The AirScan
calibrated and should require minimal adjustments
after installation. This sensor was calibrated at an
altitude of 1,000 ft. above sea level. For
installations where the altitude is greater than
3,500 feet above sea level, it is necessary to
recalibrate the sensor "span" during the initial
setup for more accuracy and reliability.
Allow the sensor to operate for 12 hours with the
enclosure sealed prior to testing the sensors. This will
give the sensor time to reach thermal equilibrium to
the external and internal temperatures while in
operation. Because sensors are normally located at a
distance from the main unit, the test time required and
accuracy of the response checks will be improved if
two people perform the start-up procedures and use
radio contact.
Start-Up Test:
1
One person exposes each sensor to a small
amount of the gas that is being monitored.
2
The second person stays at the control unit to
determine that each sensor, when exposed to
the gas fumes, is connected to the proper input
and responds, causing appropriate alarm
functions.
Figure 3. Required LED Status at Start-up
WITH OUTPUT
LED
FILTERING
POWER
G
Y
SYSTEM
OFF
CALIBRATE
Y
FAULT
R
OFF
mA FAULT
R
OFF
G
SOURCE
ON PERIODICALLY
ATMOS
G
TM
iR sensor is factory
WITHOUT OUTPUT
FILTERING
OFF
OFF
OFF
ON PERIODICALLY
7
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