Hitachi RAS-2-HVNP Service Manual page 294

8. Troubleshooting
• Checking Method of Fuse for fan motor protection (EF1)
(Measure the resistance under 1 kΩ range of a circuit tester.)
N O T E
DO NOT use a digital tester.
-
+
By placing the and side of tester to EF1 on inverter
PCB, measure the resistance.
If the resistance is 0Ω, it is normal.
  
RAS-(8-12)HN(P/C)(E)
High voltage discharge work for replacing parts
C A U T I O N
Electrical hazard. Risk of electrical shock. Perform this high voltage discharge work to avoid an electric shock.
1 Turn OFF the main switches and wait for three minutes. Check
to ensure that no high voltage exists. If LED2 is ON after start-
up and LED2 is OFF after turning OFF power source, the volta-
ge will decrease lower than DC50V.
2 Connect connecting wires to an electrical solder bit.
3 Connect the wires to terminals, P and N on IPM. => Discharging
is started, resulting in hot solder bit. Pay attention not to short-
circuit between terminal P and N.
4 Wait for 2 or 3 minutes and measure the voltage once again.
Check to ensure that no voltage is charged.
280
SMGB0079 rev.0 - 01/2013
EF1
Contact with specified terminals
Place wires to
+
to measure.
- specified terminal.
Tester
Circuit
Tester
Refer to (1)
"Detail of Check Points"
about details.
Plug
2
Solder bit
1
Connecting wires
3
Transistor module
4