Magic smoke from Harrison L5a Lathe

[The Artilleryman]

Right in the middle of doing some work my lathe decided to fail to start and a lot of noise from the contactor. On opening the access panel, I could not see anything wrong, but when I pushed the start button one of the contacts started to glow red and magic smoke was given off.

I intend to use the existing manual push buttons to operate a contactor, but don't know what makes are good and what to avoid.
It's 3 phase 1.5kw motor the contactor needs to have the buttons on the front so a linkage can be made to operate them.

 

[Brad93]

Right in the middle of doing some work my lathe decided to fail to start and a lot of noise from the contactor. On opening the access panel, I could not see anything wrong, but when I pushed the start button one of the contacts started to glow red and magic smoke was given off.

I intend to use the existing manual push buttons to operate a contactor, but don't know what makes are good and what to avoid.
It's 3 phase 1.5kw motor the contactor needs to have the buttons on the front so a linkage can be made to operate them.

Schneider

 

[Brad93]

You first need to see if your control voltage is 110v (via transformer), 230v via phase and neutral, or 440v

That will decide your coil voltage.

 

[The Artilleryman]

I thought as I was using the existing mechanical buttons on the mounting plate to push the small buttons on the contactor, that this was not relevant.

 

[Brad93]

I thought as I was using the existing mechanical buttons on the mounting plate to push the small buttons on the contactor, that this was not relevant.

Oh you want to do it like that.

Then you need to swap the contactor like for like to have any chance of the buttons lining up.

 

[brightspark]

Oh you want to do it like that.

Then you need to swap the contactor like for like to have any chance of the buttons lining up.

on an l5 thats hardly likely getting a contactor the same with its age

 

[Brad93]

on an l5 thats hardly likely getting a contactor the same with its age

Exactly my point in my original post. So op will be looking for new old stock or reclaimed.

 

[The Artilleryman]

Then you need to swap the contactor like for like to have any chance of the buttons lining up.

Not when it's the original 1970's contactor.
Plan is to make a linkage up to use the original buttons. Depending on position of buttons on the new contactor, either a small L shaped bar on the end of the existing button, or bar fixed (pivoting) at one end and connected to the button at the other with a pad or set screw pressing on the new contactor button.

I'll post photo's when done - can't use the lathe till then.

 

[Pete.]

Hopefully you'll find someone who has done a VFD conversion on their L5a and doesn't need that contactor any longer. Otherwise a button with a momentary switch and new contactor is theorder of the day because there's not usually the space in the box to fit another type of mechanical latching one.

 

[Brad93]

Not when it's the original 1970's contactor.
Plan is to make a linkage up to use the original buttons. Depending on position of buttons on the new contactor, either a small L shaped bar on the end of the existing button, or bar fixed (pivoting) at one end and connected to the button at the other with a pad or set screw pressing on the new contactor button.

I'll post photo's when done - can't use the lathe till then.

Start again from scratch, you're just on course to misery with that route.

Replacement old contactors will keep arcing out and as for making linkages, that's just making the problem more complex and time consuming.

I've got dozens of old contactors in the shed. Post a picture, i might have something, but no guarantees on its longevity,

 

[The Artilleryman]

Thanks @Brad93, I've gone for a Schneider DOL starter, quick and easy job.

 

[The Artilleryman]

The photo's show the burnt out contactor, the burn marks behind it and the new DOL starter.

Ultimately I'll take the parts out of the box and fit them behind the plate, with electrical switches behind the original push buttons. But that's for the end of the season, as I'm too busy machining parts for the miniature traction engine before the start of the rally season.