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Not a CNC problem, but hopeing someone can point me in the right direction.
This is an electrical drawing of my C3-31 Hammer (Felder) combination machine.

A few days ago it started tripping the MCB32A trip, which progressively got worse, on
any of the motors (Saw, planner, spindle moulder) until it would not work at all.

Suspected contactors, on enquiring with manufacturer was informed they only supply
complete enclosures A1 item 2 on drawing at £500.

So decided to purchase equivalent contactor and axillary contactor and fit.
Result was it would work if I unplugged the motor. (Contactor would pull in)
But if motors plunged in would sometimes work on Saw, but most of the time contactors "chattered"
some times holding in and sometimes tripping MCB332A trip.

The safety limits and stops are the same as a cnc machines so they should not be a problem.
I have tried bypassing the overload protection - no effect.

My suspicions are the braking circuit board, as I believe this works by injecting current back into
the motor to produce a magnetic field to stoop the motor quickly. Has this broken?
Causing some load to prevent the contactors working correctly?

Any help greatly appreciated before I fork out the £500.

Robert