Check
SiBE121021_C
366
Service Diagnosis
8.8
“Inverter Checker” Check
Check No.15
Characteristics
If abnormal stop occurs due to compressor startup failure or overcurrent output when using
inverter unit, it is difficult to judge whether it is caused by the compressor failure or other failure
(control PCB, power module, etc.). The inverter checker makes it possible to judge the cause of
trouble easily and securely. (Connect this checker as a quasi-compressor instead of
compressor and check the output of inverter)
Operation Method
Step 1
Be sure to turn the power off.
Step 2
Install the inverter checker instead of a compressor.
Note:
Make sure the charged voltage of the built-in smoothing electrolytic capacitor drops to 10
VDC or below before carrying out the service work.
Reference:
If the terminals of the compressor are not FASTON terminals (difficult to remove the wire on
the terminals), it is possible to connect wires available on site to the outdoor unit from output
side of PCB. (Do not connect them to the compressor at the same time, otherwise it may
result in incorrect detection.)
Step 3
Activate power transistor test operation from the outdoor unit.
1) Press the forced operation ON/OFF button for 5 seconds.
(Refer to page 440 for the position.)
→
Power transistor test operation starts.
(R13940)
(1) Remove the terminals from
the compressor.
(2) Connect the terminals to the
terminals of the inverter
checker.
Compressor
Inverter checker
Be careful not to touch the terminals
(U,V,W) each other. Otherwise, high
voltage is applied.
