Basic Troubleshooting Steps; Programming; Dc Voltage Check - Emerson Liebert iCOM Training And Service Manual

iCOM
Controls Training and Service Manual

Basic Troubleshooting Steps:

Example: Unit load is not energizing.

Programming:

1. Read and record all program parameter values.
2. Read and record all DIP (control) switch positions on all boards. Check all
jumpers on each board, check for the CAN healthy light on the boards and
check programming per the read and record sheet in appropriate manuals to
verify selected options.
3. Turn Unit off with ON/OFF button and reboot system power (disconnect switch
off - on) to reconfigure system. If programming error is detected, recheck unit
for proper operation.
If problem is not resolved in programming section, begin the signal flow check.
Signal Flow Check: Assumption is the unit is calling for a mechanical operation
but the load is not activated. Using the appropriate control training and service
manual, identify the output opto-isolator to be checked, locate the opto-isolator on
the PCB and perform the following.

DC Voltage check:

1. Using a digital voltmeter check for the correct VDC signal at the output opto-
isolator. Pin 1 referenced to - VDC will show low VDC (approximately 1.2
VDC) if the microprocessor control side of the device is functioning. A high
VDC (approximately 3.3 VDC) indicates a microprocessor control problem. A
meter reading of 0 VDC indicates a loss of microprocessor voltage, check VDC
at the power supply referenced +VDC to -VDC should be approximately 3.3
VDC.
2. This check involves the microprocessor. To bypass the microprocessor
completely, jumper from Pin 2 on the output opto-isolator to -VDC. As soon as
the jumper is applied the load device should activate. If the load device
activates the problem is in the microprocessor itself or the programming. If the
load device does not activate continue the signal flow check.
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