Harrison L6 main contactot

Just tried to turn on my Harrison L6, Turning on main rotary switch and overhead light comes on.Pushing motor start contactor  switch is met with the dreaded sound of silence.My guess a dead contactor. Any ideas? Modern equivalent?

Edited By john landonbrowne on 16/03/2023 12:56:11

phewwwwwwwwwwwwwwwwwwwww got it The contactor unit had slipped on its mounting stopping the "on" button from operating the hold down solenoid.

Would still like a spare contactor

If it's the old style MEM unit with an auto - manual switchable reset overload detection device it's worth verifying the unit hasn't decided to switch all on its ownsome for no discernible reason.

Such self switching after many years of doing nothing at all is a known, albeit moderately rare issue. A goodly spray with switch cleaner and operating the auto - manual switch a few times sorted one on my Bridgeport about 7 years ago. Sill going strong. If it happens again the whole lot are coming out to be replaced by modern mid-range DIN rail relays.

It may also be simply dirty contacts on the coil switching side. Old style MEM and similar vintage are relatively easy to strip and clean. Coil control contacts only carry a small current and tend to be little vulnerable to contamination over the years.

If it really has died, basically coil going open circuit is the only thing that will permanently kill an old one, as opposed to too much futzing to fix, get a short piece of DIN rail and a mid-range DIN fitting replacement. Anything from an industrial supplier or brand you have heard of will do. Probably around £30 to £50 the pair. CHINT come up as cheapest contactor at around £15, I have some off their other products which seem OK. Would be willing to try one although my last such purchase was Schneider.

Clive

Edited By Clive Foster on 16/03/2023 13:26:00

It was a simple mechanical failure,the main contactor unit has shifted sideways enough to stop the front panel mounted push buttons from getting a clear operating path