[8-11 Troubleshooting Inverter Problems (YKMU) ]
Simple Check on Inverter Circuit Components
Before inspecting the inside of the control box, turn off the power, keep the unit off for at least 10 minutes, and confirm that
the voltage between FT-P and FT-N on INV Board has dropped to DC20V or less.
Refer to the following page(s). [8-11-14 Troubleshooting Problems with IGBT Module](page 305)
Rush current pro-
Measure the resistance between terminals R1 and R5: 22 Ω±10%
DC reactor DCL
Measure the resistance between terminals: 1Ω or lower (almost 0 Ω)
Measure the resistance between terminals and the chassis: ∞
Troubleshooting Problems with IGBT Module
Measure the resistances between each pair of terminals on the IGBT with a tester, and use the results for troubleshooting.
The terminals on the INV board are used for the measurement.
1) Notes on measurement
Check the polarity before measuring. (On the tester, black normally indicates plus.)
Check that the resistance is not open (∞ Ω) or not shorted (to 0 Ω).
The values are for reference, and the margin of errors is allowed.
The result that is more than double or half of the result that is measured at the same measurement point is not allowed.
Disconnect all the wiring connected the INV board, and make the measurement.
2) Tester restriction
Use the tester whose internal electrical power source is 1.5V or greater
Use the dry-battery-powered tester.
(The accurate diode-specific resistance cannot be measured with the button-battery-powered card tester, as the applied volt-
age is low.)
Use a low-range tester if possible. A more accurate resistance can be measured.
This electromagnetic relay is rated at DC12V and is driven by a coil.
Check the resistance between terminals
Between Terminals 5 and 6
Between Terminals 1 and 2
Between Terminals 3 and 4
- 305 -
Checking criteria( )
Not to be short-circuited
(Center value 75 ohm)