Replacing the New INV-BDC Elevator Board Steps

Normally, if the INV-BDC elevator board on the elevator is damaged, the high-power transistors (IGBT modules) connected to the BDC are likely damaged as well.
Before installing the new BDC board, it is recommended to check the IGBT module — QM300HA-H (MVP type) or QM200HA-2H (HVP type).

If the module is damaged, installing the new board may result in damage to the replacement INV-BDC elevator board.

Additionally, if the two 5600μF capacitors have been in use for a certain period, they must be replaced as well.

The failure or degradation of these capacitors is highly likely to be the cause of the BDC board malfunction.

Installation Steps for the New INV-BDC Elevator Board (Elevator):

1. Before powering on, disconnect the elevator safety circuit to place the elevator in inspection mode.

2. After power is on, measure the voltage between B (base) and E (emitter) of each high-power GTR transistor, and ensure that a negative gate-off voltage is present — approximately -3.3V.

3. Make sure the INV-ACRA and INV-MPU boards are both in good condition before performing the low-speed jog test. Only if the low-speed jog test passes successfully should you proceed with the high-speed operation test.