3ph Sedgwick LK saw spinning in reverse

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wthrelfall

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I recently bought a used 3ph Sedgwick LK table saw with Crompton S10 brake. It was running well when I picked it up, but on my first switch on at my own workshop (with a new 5.5hp rotary phase converter) the blade is running in reverse. I checked the wiring in the 3ph plug which was L1 terminal > wire 1, L2 > 3, L3 > 2. I thought this might be the reason so swapped the L2 and L3 wires round and tried it again. This time the saw tries to start in the right direction but quickly stops. If anyone has any experience with this kind of problem I'd love to know!
Ps. I also purchased a Sedgwick PT260 3ph planer (with S10 brake) which was working on collection, but won't turn on in my shop.
 

nickds1

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Silly question: are you sure the phases in your workshop are labelled correctly?

Secondly: is the motor wired correctly to match the type of 3 phase in your workshop, i.e. Wye/Y (4 wire) or Delta (3 wire)?
 
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Spectric

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You have a three phase supply so should not have problems but before swaping phases check from the convertor that L1(Brown) , L2(Black) and L3(Grey) run through any boards and connectors on the right pins, I have seen installations where people have swapped over phases to correct a non existant problem and then have swapped it back elsewhere so end to end bells out ok but a right mess inbetween.

If this is all correct then your problem could well be with the brake circuit, without a diagram it is impossible to tell and I have not done much work on these convertors, having used digital phase convertors in preference. Thinking about the supply, the brake and control wiring need to be on the same phases with a rotary convertor due to the nature of the supply, I believe not on the created third line but again you need a diagram.
 

guineafowl21

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Put it all back as it was, then open up the DC brake and swap two phases where the motor joins the contactor, at the bottom.

Adjust the braking time and force pots right down. Check the current setting on the overload - set it to somewhere (say 20%) above the full load amps on the motor rating plate.

Assuming it works, then adjust the time pot so the braking time is ten seconds, then adjust the force pot so the blade comes nicely to rest just within that time, with the saw blade fitted.
 

wthrelfall

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Thank you! Without reading any of these generous replies, I was studying the S10 brake unit and came to the conclusion that swapping the phases as described by guineafowl would be a possible fix, although I was hesitant to do it based on my own assessment! I will follow this great advice and see how it goes.
 

wthrelfall

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Saw is all good now, thanks for that!
Now I'm trying to figure out why the planer doesn't work. It has the same S10 brake and I have wired it from the Rotary phase converter in the same way as the saw, but still nothing. I did see it working the day I picked it up so I'd be surprised if it's developed a problem in that time.
Any thoughts?

Put it all back as it was, then open up the DC brake and swap two phases where the motor joins the contactor, at the bottom.

Adjust the braking time and force pots right down. Check the current setting on the overload - set it to somewhere (say 20%) above the full load amps on the motor rating plate.

Assuming it works, then adjust the time pot so the braking time is ten seconds, then adjust the force pot so the blade comes nicely to rest just within that time, with the saw blade fitted.
 

guineafowl21

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Saw is all good now, thanks for that!
Now I'm trying to figure out why the planer doesn't work. It has the same S10 brake and I have wired it from the Rotary phase converter in the same way as the saw, but still nothing. I did see it working the day I picked it up so I'd be surprised if it's developed a problem in that time.
Any thoughts?
Does the contactor in the S10 pull in?
 
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