Inspection Method 1 - Hitachi RAM-90QH5 Service Manual

Inspection method 1

Insert the power source, and check to see that the
LED is on.
Is AC230V voltage reading at L/N terminal?
Yes
Is the 30A fuse working normally?
Yes
Is the 5A fuse working normally?
Yes
The control P.W.B. is broken.
Replace the control P.W.B.
LED off
No
Check to see that varistors 1-3,
diode stacks Act Module,
IPM Board are not broken.
No
Is varistor 2 broken?
There is the possibility that an irregular voltage has been
flowing to the L/N terminal. Check to see that the power
source is not abnormality.
Replace the 5A fuse and varistor 2.
LED on
Follow "Inspecting outdoor electrical parts" and check
the cause of the problem.
No
Connect a commercial-use 220-240V power source
to the L/N terminal.
Yes
– 77 –
Replace the broken part
and the 30A fuse.
No
The control power source is broken.
Replace the control P.W.B.