[8-9 Troubleshooting Inverter Problems ]
8-9-14
Simple Check on Inverter Circuit Components
Turn off the power of the unit and wait at least 10 minutes, check that the voltage between the FT-P and FT-N terminals on
the INV board or between the SC-P and SC-N terminals is 20 VDC or less, and then remove the applicable parts from the
control box.
Part name
IGBT module
Refer to the following page(s). [8-9-15 Troubleshooting Problems with IGBT Module](page 273)
Measure the resistance between terminals R1 and R5: 22 Ω±10%
Rush current pro-
tection resistor
R1, R5
Electromagnetic
relay
72C
P200-P400
P450-P500
Measure the resistance between terminals: 1Ω or lower (almost 0 Ω)
DC reactor DCL
Measure the resistance between terminals and the chassis: ∞
8-9-15
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.
HWE14040
This electromagnetic relay is rated at DC12V and is driven by a coil.
Check the resistance between terminals
Upper
1
2
3
Installation
direction
6
4
3
1
2
Judgment method
4
Check point
Between Terminals 5 and 6
Coil
Between Terminals 1 and 2
Contact
Between Terminals 3 and 4
5
Check point
Coil
Between 1-2 pins and inverter
RY3-RY4
boards RY3 and RY4
Inverter board FT-R21 and SC-P
Contact
*Faston terminal and SC-P
RY3-RY4
wiring removed
- 273 -
Checking criteria( )
W
Not to be short-circuited
(Center value 75 ohm)
Checking criteria
160Ω±10%
Inverter board CNRY
Open: ∞
Inverter board CNRY
When 12 VDC is being input: 0Ω
GB