problems with chattering contactors

I have a three phase forward/reversing drill press that runs in each direction. However the contactors for each direction recently started
buzzing or chattering rather loudly. I have already checked for obvious wiring problems. What are some causes for the loud buzzing? Sincerely, Steve
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Delamination of the contacts is the usual culprit. Are the contactors getting hot?
Eventually the contactors will fail (your drill press won't work) and you'll have to get them replaced.
HTH, Cameron:-)
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Dirty pole faces ?
sQuick..
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sQuick wrote:

A common problem no less, but not caused by bad contacts of the chattering contactor! Check the control contacts upline from the chattering Contactor (switchs or relays). Most likely, too much resistance in the operating coil circuit which causes low voltage & high current. use a meter to measure the inrush current.
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