4A MCB Tripping on Power On with 24VDC 6.5A SMPS After Magnetic Contactor Switch

Hi Experts,

Need your help.
I have Circuit where by my hardwiring is swicting my Magnetic contactor.
After Contactor switching the 3-Phase AC voltage is split to Two Single Phase.
One Tapping goes to MCB16A C curve 1.5kw Servo Motor driver and Another Tapping to MCB 4A C CURVE

During Initial Power ON my contactor Coil turns On and it causes my 4A MCB to trip.

This 4A MCB is connected to Switch mode power supply 24vdc 6.5A,Which has rated current of AC 2.1A at 100% LOAD.

Not sure why it causes my 4A MCB to trip during Initial Power On/Off.
Please find the attach for more details.

Appreciate your comments and suggestions.

PowerCircuit5

Hi Ankim,

Have you tried replacing the 4A MCB?

or

Try checking the line if there is a faulted part.

Hope it helps.

Best,
Neil

Hello Mr.Neil,

I did check MCB and other parts.But the problem is only during initial power On/Off.

Thanks,
Ankim

Hi Ankim,

Well, in that case you should increased the current rating value around 6A-10A MCB.
If it trips again, you have a faulted circuit.

Try to redesign the connection.

Hope it helps.

Best,
Neil