TCM FB-8 Series, Service Manual

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2. ELECTRICAL PARTS AND PROCEDURES FOR CHECKING
Checking procedure (using an analog multimeter)
①
Measure the resistance of each terminal according to the table given below using an analog
multimeter with the resistance range set to x1000 ohms.
②
Determine whether the inverter unit is defective or not according to the resistance value measured
at each terminal.
Standard value for each terminal on the inverter unit
Measurement
point
Multimeter Normal value
Judgment
Red probe (+) Black probe (-)
Approximate
reading
VB-U
VB U 2 or 3 kΩ Defective if 0 Ω or ∞ Ω
U VB
2 or 3 kΩ to
∞ Ω
The judgment varies according to charge
status of the capacitors in the main
circuit; defective if 0 Ω is seen.
VB-V
VB V 2 or 3 kΩ Defective if 0 Ω or ∞ Ω
V VB
2 or 3 kΩ to
∞ Ω
The judgment varies according to charge
status of the capacitors in the main
circuit; defective if 0 Ω is seen.
VB-W
VB W 2 or 3 kΩ Defective if 0 Ω or ∞ Ω
W VB
2 or 3 kΩ to
∞ Ω
The judgment varies according to charge
status of the capacitors in the main
circuit; defective if 0 Ω is seen.
U-N
U N 2 or 3 kΩ Defective if 0 Ω or ∞ Ω
N U
2 or 3 kΩ to
∞ Ω
The judgment varies according to charge
status of the capacitors in the main
circuit; defective if 0 Ω is seen.
V-N
V N 2 or 3 kΩ Defective if 0 Ω or ∞ Ω
N V
2 or 3 kΩ to
∞ Ω
The judgment varies according to charge
status of the capacitors in the main
circuit; defective if 0 Ω is seen.
W-N
W N 2 or 3 kΩ Defective if 0 Ω or ∞ Ω
N W
2 or 3 kΩ to
∞ Ω
The judgment varies according to charge
status of the capacitors in the main
circuit; defective if 0 Ω is seen.
*1. The values in the “Normal Value” column should be used as a rough guide, because they may vary with the type of multimeter used
and battery’s internal state of charge.
*2 If a digital multimeter is used, the resistance between each terminal will usually show a reading of 20 to 30 kΩ as a normal value.
However, in this case too, the value may vary with the type of multimeter and the battery’s internal state of charge.
If the resistance is 0 Ω, a digital multimeter will read between 0 and 20-30 Ω.
Notes
Apply a heat-dissipating silicone compound (KS-609: Shinetsu Kagaku) over the whole back-surface
•
of the inverter unit.
Make sure to apply the silicone compound whenever the inverter unit is replaced with a new one, to
•
allow the heat generated by the inverter unit to be transmitted to the aluminum base efficiently.
Make sure there is no metal powder, cuts, damage or burrs on the mating surfaces of the aluminum
•
base and the inverter unit before applying the compound.