Inverter Board (Inv Board) - Mitsubishi Electric PUHY-M200YNW-A1 Service Handbook

[4-6 Hydro Unit Circuit Board Components ]
4-6-3

Inverter Board (INV Board)

SC-R
Input (L)
SC-T
Input (N)
1) When opening or closing the front panel of the control box, do not let it come into contact with any of the internal 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 across pins 1 and 5 of connector RYPN has dropped to 20 VDC or less. It takes about 10 minutes to discharge
electricity after the power supply is turned off.
2) A Faston terminal has a locking function.
Make sure the cable heads are securely locked in place. Press the tab on the terminals to remove them.
3) Control box houses high temperature parts. Be well careful even after turning off the power source.
4) When the power is turned on, the water pump is energized even while it is not operating. Before turning on the power, discon-
nect all power supply wires from the water pump connector, and measure the insulation resistance of the water pump.
Check the water pump for a ground fault. If the insulation resistance is 1.0 MΩ or above, connect all power supply wires to the
water pump and turn on the power to the hydro unit.
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chapter 4
LED 4
Lit: Microcomputer is energized
Unlit: Microcomputer is not energized
SC-U
Inverter output (U)
LED 1
Lit: Inverter operation
Unlit: Inverter error
SC-W
SC-V Inverter output (W)
Inverter output (V)
BS_04_E