Hitachi Breaker fault.

Smallfry · 2026-02-13T19:25:47+0000

Pulled out the old Hitachi Electric breaker to use today, not used for a couple of years.

Heavy sparking at the brushes, and a noise like a welder. Also getting warm quickly. Brushes looked OK but tried another set anyway after cleaning the armature a bit.

Still the same. I guess this is the armature ? I can't see any damage, but any ideas how to test them, or could it be something else ?

Its about 25 years old, but worked well, but probably not worth spending money on, despite being a £500 odd machine

Agroshield · 2026-02-13T19:49:30+0000

Can you write down the model number and voltage. Then, just for reference, we can chck availability and price of an armature.

I think you can check continuity or not between pairs of commutator segments. I do not, however, know what a 'good' result should be.

Cobbler · 2026-02-13T20:00:18+0000

Is there a motor rewind place near you, they can put it on a magnetic device, I think they call it a growler to test.

brightspark · 2026-02-13T20:34:47+0000

if its sparking round the commy its knacked

Smallfry · 2026-02-13T22:38:56+0000

Agroshield said:
Can you write down the model number and voltage. Then, just for reference, we can chck availability and price of an armature.

I think you can check continuity or not between pairs of commutator segments. I do not, however, know what a 'good' result should be.

Its a Hitachi H55 SA Label says 230 volts, but we are on 242 volts here