Sparking brushes of Synchronous Motors
Sparking brushes of Synchronous Motors
(OP)
I have two identical 4000hp Synchronous Motors operating reciprocating compressors. The '–ve' terminal brushes on one machine tend to develop spark. The excitation control system (GE-Stat-x-ator) has almost the same volts/amps/pf for each machine, as the loading is identical. Need help to find root-cause for the carbon-brush spark?





RE: Sparking brushes of Synchronous Motors
rough slip ring causes bouncing
not enough spring tension
brush face condition
Is it a condition that developed over time?
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RE: Sparking brushes of Synchronous Motors
RE: Sparking brushes of Synchronous Motors
RE: Sparking brushes of Synchronous Motors
RE: Sparking brushes of Synchronous Motors
Bill
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Jimmy Carter
RE: Sparking brushes of Synchronous Motors
RE: Sparking brushes of Synchronous Motors
Muthu
www.edison.co.in
RE: Sparking brushes of Synchronous Motors
Another client had problems with only one brush of the two on one slipring arcing. The problem was that the installer had not installed a jumper to equally share the current between the two brush-holders.
Another problem surfaced when we found that an ambitious electrician had "re-sized some off the shelf brushes from generator exciter service to make them fit the synchronous motor application. After all, it was "all black carbon, right?" Wrong composition=arcing.
old field guy