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3
Operation
STEP 1
4-20 mA Output Calibration
This procedure calibrates the 4/20 mA output to match
a PLC input converter or various devices that interpret
the 4/20 mA signal output to ensure the 4 mA output
rests at a true 4 mA even with minor mismatches in
load resistance, long feed wiring, or adverse
environmental conditions.
Start: Set meter to mV DC and place meter leads on
Test(+) and Test(—) respectively (see Figure 9).
•
Press and hold the "zero" button (S1) for 5
seconds or until the "calibrate" LED is blinking
slowly and the "system" LED is continuous ON.
Make sure the "mA Fault" LED is OFF.
•
Adjust the zero potentiometer until the output
reads 3.99 to 4.01 mA (39.9 to 40.1 mV). This
sets the 4 mA resting point. Make small
adjustments and wait for the output to change
because adjustment response is delayed
between source pulses.
4 mA output programming calibration mode
LED
SEQUENCE
G
POWER
SYSTEM
Y
CALIBRATE
Y
FAULT
R
mA FAULT
R
G
SOURCE
ATMOS
G
Exit: Press and hold the "zero" button (S1) for one
second or more until the "calibrate" LED turns off.
The "system" LED will resume the previous state,
either "filtered" or "non-filtered" output mode. This
indicates the parameters are now programmed into
memory.
Manning AirScan-iR Refrigerant Sensor
continued
N/A
OFF
N/A
N/A
19100 AirScan-iR-ind 05/2006 REVA Copyright © 2006 Manning Systems, Inc. All Rights Reserved.
STEP 2
Zero Calibration
This procedure sets the internal reference that is
indicative of 0 ppm of target gas. It MUST be
performed before proceeding or every other setting
will be offset and inaccurate. The "zero" can be
initiated at any time as long as a neutral gas is flowing
through the calibration port or the surrounding air is
known to be FREE of any target gas down to 1 ppm.
Start: Apply pure nitrogen (N
port at a rate of .6 liter/min. for at least 3 minutes (OR
until output signal is within ± .02 mA of signal
deviation/change).
•
Press and hold the "zero" button (S1) for
approximately 1 second or until the yellow
"calibrate" LED is continuous ON.
•
When yellow calibration LED is continuous ON,
release the "zero" button. The "calibrate" LED
will turn off and the unit will be zeroed. See
example below.
"Zero" programming calibration mode
LED
SEQUENCE
POWER
G
SYSTEM
Y
N/A
Y
CALIBRATE
R
OFF
FAULT
OFF
mA FAULT
R
SOURCE
G
N/A
ATMOS
G
N/A
Exit: System will automatically resume previous mode,
either "normal" or "no dead band" mode. This indicates
the parameters are now programmed into memory.
Place multi-meter leads on Test(+) and Test(—) and
ensure the output is steadily resting between 3.9 to
4.1 mA (see Figure 9 on next page). If this isn't the
case, initiate the auto "zero" procedure once again.
) into the calibration
2
17
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