MCi iControl User Manual page 346

Troubleshooting
Table 6.3 iControl Messages
SCR Excessive Current Command, Drive Enabled, SCR EXS CURRENT CMD DE
Description: Current command output greater than 7VDC within 300mS after enabling the run enable relay,
drive enabled. DC controls only.
Car Reaction: Car will not run.
Troubleshooting:
1. Check serial cable between iBox and drive.
2. Check SCR-LGA board (section 8).
SCR High Temp Fault, SCR HIGH TEMP FAULT
Description: This fault indicates that either the ambient temperature inside the System 12 drive has
exceeded 170 degrees F or there is a bad or failing SCR. iControl will attempt to bring the car to the nearest
floor before shutting down. The fault clears when the temperature drops below tripping threshold. DC con-
trols only.
Car Reaction: Stop at nearest floor. Car out of service until fault cleared.
Troubleshooting:
1. Check for excessive ambient temperature.
2. Check for insufficient air flow through the drive, especially if the fault is generated when the car is run-
ning and clears when the car is stopped. Verify that the fan is operating properly. Check the fan fuse.
3. Check for bad or failing SCR.
4. Check for defective fault-generating thermostat. There are two heat sensors, one on each heat sink.
Check the integrity of the heat sensor's normally closed contacts.
5. Check the drive's rated armature current to determine if it is operating close to the limit threshold.
Please refer to "Current Limit Adjustments" in Section 2.
SCR Instantaneous Over Current, SCR INST OVER CURRENT
Description: This fault indicates that the System 12 SCR Drive detected excessive armature current. DC con-
trols only.
Car Reaction: Emergency Stop.
Troubleshooting:
1. Check that the main supply is being shut off during regeneration.
2. Check for a clipped door lock.
3. Check for a motor connection problem.
4. Possible failure of an SCR in the System 12 Drive.
SCR Insufficient Armature Current, SCR INSF ARM CURRENT
Description: This fault indicates that insufficient armature feedback current has been detected. This fault is
generated if the requested current is at least 20% of the rated armature current yet the detected feedback
remains below 10% of the rated armature current. Automatically resets if detected four or fewer times in
seven consecutive runs. DC controls only.
Car Reaction: Emergency Stop.
Troubleshooting:
1. Check Armature Voltage Limit and Armature Current Limit settings on iView/Drive/Safety.If this fault
occurs when the car is running at speed, adjust Motor Field so that armature voltage is within rated
motor armature voltage.
2. Verify current sensor connection on SCR-LGA board (section 8). Check SCR-LGA board.
3. Check serial cable from drive to iBox.
4. Monitor the Up and Down direction inputs on the SCR-LGA board (bottom of R14 down, bottom of R22
up). If there is a momentary drop in the direction signal before the run is complete, use jumpers to
determine if a section of the safety string is failing. WARNING: The car must be on Independent Service
before performing this test.
5. If the failure persists from the beginning of the run, make sure the current signal on SCR-LGA board test
point TP3 is not dropping out.
6-70 Manual # 42-02-2222
iControl Messages