Ma Low Signal Output Test For Fault Conditions - Honeywell Manning AirScan iR Instruction And Installation Manual

AirScan iR - Industrial
Figure 30. During 4-20 mA loop test (22 mA high) w/error on output
0.5 mA Low Signal Output Test for Fault
Conditions
NOTE: The unit must be in the 4/20 mA loop (22 mA
high) test to proceed with this test.
STEP 2
Start: Press and hold the "zero" (S1) button for at least
one second or until the yellow "calibrate" LED shows
medium double blink. The yellow "system" LED will
remain off and the output should change to .4 to .6 mA
(4 to 6 mV).
If a problem exists on the output signal line, or the
output load is not within the specified range, the "mA
fault" LED will blink either before or upon activation of
this test.
If an error surfaces during this test only, the possibility
of cross-talk can exist on the signal line. This is
caused by resistive shorts to power or other voltage
sources that can raise the .5 mA target current on
the line. Moisture in the connector can cause stray
voltage to migrate from the 24V DC pin over to the
4/20 mA signal line. Check connectors or refer to the
troubleshooting section or error code analysis section
for assistance.
20
Figure 31. During 4/20 mA loop test (0.5 mA low)
Figure 32. During 4/20 mA loop test (0.5 mA low) with error
STEP 3
Exit: Press and hold the "zero" (S1) button for at least
one second or until the yellow "calibrate LED turns
off. The yellow "system" LED will resume the previous
state, either "filtered" or "non-filtered" output mode.
NOTE: In addition to test procedures initiated
manually, every 2 seconds SensorCheck
monitors several performance parameters of the
AirScan iR. A notification of 0.5 mA on the output
TM
signal is transmitted if any of these parameters is not
met.
technology
TM