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Table 3-7 Controller Pre-Trip Test Codes (Sheet 2 of 6)
P4 Tests - High Speed Evaporator Fans Current Draw:
High speed evaporator fans are turned on, then off.
Current draw must fall within specified range and measured current changes must exceed specified ratios. No
other system components will change state during this test.
NOTE
If unit configured for single evaporator fan operation and either AL11 or AL12 is active at the start of either
test, the test will fail immediately. If AL11 or AL12 become active during the test, the test will fail upon conclu-
sion of the test.
P4-0
High Speed
Evaporator Fan
Motors On
Evaporator fans start in the off condition, current draw is measured, then high
speed evaporator fans will be turned on. After 60 seconds the current draw is
measured again. The change in current draw is then recorded.
Test passes if change in current draw in the specified range AND measured cur-
rent changes exceed specified ratios.
If the three phase motors are configured IN, the change ratio test is skipped.
P4-1
High Speed
Evaporator Fan
Motors Off
High speed evaporator fans are then turned off. After 10 seconds the current
draw is measured. The change in current draw is then recorded.
Test passes if change in current draw test is in the specified range.
P5 Tests - Air Stream Temperature Sensor Tests:
Tests the validity of the Air Stream Temperature Sensors.
P5-0 Supply / Return
Probe Test
The High Speed Evaporator Fan is turned on and run for eight minutes, with all
other outputs de-energized. A temperature comparison is made between the
return and supply probes.
Test passes if temperature comparison falls within the specified range.
NOTE
If this test fails, “P5-0” and “FAIL” will be displayed. If both Probe tests (this
test and the PRIMARY / SECONDARY) pass, the display will read “P5”
“PASS.”
P5-1
Supply Probe Test
This test if for units equipped with secondary supply probe only.
The temperature difference between primary supply probe and secondary supply
probe is compared.
Test passes if temperature comparison falls within the specified range.
NOTE
If this test fails, “P5-1” and FAIL will be displayed. If both Probe tests (this
and the SUPPLY/ RETURN TEST) pass, because of the multiple tests, the
display will read ’P 5’ ’PASS’.
P5-2
Return Probe Test
For units equipped with secondary return probe only.
The temperature difference between primary return probe and secondary return
probe is compared.
Test passes if temperature comparison falls within the specified range.
NOTES
1. If this test fails, “P5-2” and “FAIL” will be displayed. If both Probe tests
(this test and the SUPPLY/ RETURN) pass, because of the multiple
tests, the display will read “P 5,” “PASS.”
2.
The results of Pre-Trip tests 5-0, 5-1 and 5-2 will be used to activate or
clear control probe alarms.
P5-3
−
P5-9
Not Applicable
P5-10
Humidity Sensor
Controller
Configuration
Verification Test
This is a Pass/Fail/Skip test of the humidity sensor configuration.
Test passes if the controller configuration has humidity sensor in.
Test fails if the controller configuration has humidity sensor out and Vout is great-
er than 0.20 Volts for the humidity sensor.
Test is skipped if the controller configuration has the humidity sensor out and
Vout is less than 0.20 Volts. Unit must be configured with a Humidity Sensor for
this test is run.