E.sc Fault - Veichi AC310 Service Manual

AC310 Universal AC Drive Service Manual
Measurement method: Measure according to the measurement method of IGBT module
Solution: Replace the IGBT module.
2. Failure of the current detection circuit on the power supply board
Cause: Failure of the circuit (failure of the current detection chip, Hall device, current
detection resistor circuit), which causes the collected current to fail, causing the CPU
to make incorrect judgment.
Measurement method: Detect according to the current detection circuit method.
3. Failure of the OC comparison circuit on the control board.
Cause: Circuit failure, resulting in CPU judgment error.
Measurement method: Test according to the OC comparison circuit maintenance
method.

4.4 E.SC Fault

1. IGBT module short circuit
Cause: IGBT module AC drive short-circuit, phase to phase short-circuit, resulting in
excessive current to report OC.
Measurement method: Measure according to the measurement method of IGBT
module.
2. Electromagnetic interference
Cause: The existence of electromagnetic interference leads to problems in the
transmission of weak electrical signals from the control board, thus reporting E.SC
failure. Solution: Ground the wire, and then the interference flows out through the earth.
3. Current detection chip failure
In the current detection circuit of the power supply board, we mentioned that the current
detection chip fast protection feet VOC_F and FAULT_F/ When the current reaches
the set overcurrent point, the chip sends out a FAULT low-level signal within 1.5us,
and connects this signal to the FAU function foot, so that the system reports SC
protection.
4. The direct cause of E.SC failure is that the FAU signal is pulled down. The normal
FAU signal is high, and when the FAU goes low, the CLOSE signal goes high, blocking
the driver output.
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