Hitachi YUTAKI Series - Checking Capacitors CB1 & CB2

Troubleshooting
Service Manual
222
Checking procedure for main parts
SMGB0066 rev.0 - 12/2009
 
1.Bybonding+Pto-UVWor-Nto+UVW,nocontinuityandnovariationonvoltagedropshouldappear.
2.Bybonding-Pto+UVWor+Nto-UVW:continuityandvariationonvoltagedrop(nearly0,405)shouldbedisplayed,
and the same value in all cases. Not the same value means that the diode module is damaged.
 

danger
Electrical hazard. Risk of serious injuries or death. -
Before installing the electrical wiring or before performing a periodical check, turn OFF the main switch of the -
unit. For safety reasons, be sure that the fan is stopped.
Prevent from touching the capacitors’ terminals. High voltage should be present before discharging them. -
Turn off the unit and wait for the LED 201 to be off before touching the components. -
Ifit’spossible,checkthecapacitanceofeachcapacitor:4700μF±20%(between3760μFto5640μF).
A visual check of the pressure valve of capacitors must be done to ensure it’s integrity:
It is not recommended to check tension.
PN=Powersourcex√2,PC=CNisnearlyequaltoPN/2.
R1 & R2:
1) If the value is different:
- Capacitor could be damaged by overload.
- 04 alarm could be displayed if low supply voltage (CN) for ISPM control part is present.
2)R1=9.5Ω&R2=14.0Ω.Ifthesevaluesaredifferent,thecapacitorswillbenotproperlycharged.
ResistancebetweenP1&TB3=2kΩ(whiteresistanceintheISPM).