View Full Version : Smoked a contactor , but why?

26-03-2015, 06:14 PM
Hi All , Bench testing my safety setup (Pnox x1 based) and was not sure if the X1 would handle the current since I plan to switch spindle (Kress 1050) and all the stepper supplies . So I decided a contactor would be a smart move

Except with a few moments of the contactor being energised it started to smoke , what I am I doing wrong ....

Clive S
26-03-2015, 06:33 PM
Have you got the numbers correct on your drawing as they appear different than the one in the Farnell Cat. you don't give enough information like the voltage of the contactor coil ac or dc etc. The Farnell site show the reset on Y1 and Y2 ..Clive

26-03-2015, 08:16 PM
http://www.mycncuk.com/attachment.php?attachmentid=15009&stc=1a cleaner drawing attached this time

Hi , Clive thanks for looking , the reset is on Y1 and Y2 as per diagram on the RS site and Pilz's own datasheets - I confess in the drawing as it does look bit like it's connected to X1 (its not)

The Contactor should have been 24V dc .... at least thats was I ordered on ebay ....but looking deeper at it has 24v 50Hz written on it .. so ac?

Which would explain the smoke :(

Clive S
26-03-2015, 10:04 PM
Quite possibly :beer: Clive

27-03-2015, 02:25 PM
Yep it's an AC coil same thing happened to me when was sent AC coil by mistake. I use these Chana Contactors all the time and very easy mistake to make as there are very little to no markings on the Contactor other than 50hz to give it away.

27-03-2015, 06:10 PM

When you have the correct contactor (24 volt dc) you need to put +24 volt onto terminal 13 of the PNOZ X1 then out on pin 14 this then goes to to A1 on your contactor and A2 to your zero volts so when your safety relay is reset this will then pull in the contactor. When you press the e stop this will then drop the contactor out.


27-03-2015, 06:58 PM
Hey Up Stranger!!! . . . Andy he does have it drawn that way but I see A2 (0v) on the contactor is connected to 24V which is wrong is that what your meaning.?

27-03-2015, 08:11 PM
Hey up Dean

The way he has it drawn is +24v terminal 13 terminal 14 to A1 then terminal A2 back to +24V ?

I have to keep my hand in, might not post a lot but lurking in the background keeping an eye on you ; )

27-03-2015, 08:42 PM
I have to keep my hand in, might not post a lot but lurking in the background keeping an eye on you ; )

It's Ok DAD I'm being a Good boy these days I've not been in trouble for months.!!. . . Lol (Not Same with out Jon & John around nobody to Whind Up . .lol)