Noisy,buzzing contractor

[Pete999]

Chattering contactors, many time in my time it was down to dirty pole faces on the magnetic part of the contactors , worth checking for grease and poor alignment on the magnetic side of things.

 

[Steviec1]

Chattering contactors, many time in my time it was down to dirty pole faces on the magnetic part of the contactors , worth checking for grease and poor alignment on the magnetic side of things.

If it's brand new and chattering, check coil voltage and actual voltage being supplied.
It may be fault in retaining circuit.
Turn off DB and recheck for buzzing.
Turn off all circuits in DB.
Re-engage DB and introduce circuits one at a time.

 

[pc1966]

If you have space for some DIN rail then a MCB for the control feed is an obvious route to protection, or an HRC fuse using something like this:

DF101 | Schneider Electric Rail Mount Fuse Holder for 10 x 38mm Fuse, 1P | RS

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