So Why Doesn’t My Contactor Work?

[Seven-Delta-FortyOne]

Direct replacement. Here is what was there:



Here is what I installed:




Good power coming in. Good power to the timer. Good power to the line side of the relay.

When I set the timer for on, I hear a faint click, but the Contactor never closes.

I tried switching the DC input on the A1 and A2 inputs, just in case, and still the same.

I put a meter on the output of the relay, and didn’t get any voltage. I believe I should have 12 or 24v. I believe the relay is bad. Anything else I’m missing?

And why doesn’t ABB contactors have a way to close the Contactor manually?

 

[AC\DC]

Could you post pictures where I could read the nameplate and in my ignorance what do you mean manual on the Abb’s? You can press those in manually

 

[Master Nater]

and one showing your test leads on the coil, as well as the voltage they are being fed.

 

[tortuga]

I tried switching the DC input on the A1 and A2 inputs, just in case, and still the same.

DC input is that a typeo? Looks like a 120 VAC system.

 

[Seven-Delta-FortyOne]

So I started thinking about this and I wondered if maybe it isn’t a LV DC input. Apparently the last one was.

The info shipped with the Contactor is less than worthless, so I actually don’t know if it is line or low voltage input.

The white uh, button, for lack of a better word, in the center of the contactor does nothing. Usually you can manually close it with the button.

and one showing your test leads on the coil, as well as the voltage they are being fed.

Voltage is 208Y, little hot but nothing crazy. Phase to ground is 123-124, P-P 214 and 215.

I just bypassed the contactor for the time being so the parking lot lighting will on over night and it works fine.

 

[AC\DC]

DC input is that a typeo? Looks like a 120 VAC system.

Ya was wondering about the original contractor information

 

[brycenesbitt]

How broken is the old one, and what could you learn putting it back
in temporarily, and measuring the control voltage / current ?

 

[hbiss]

Looks like there is a lot going on with that original contactor. I see a big high power resistor and other stuff on top of it in that top photo. Makes me wonder if it's just a contactor, it does say "remote control switch".

Do you measure an AC or DC voltage on the coil leads of the original contactor. What is it? What is the coil on your new contactor?

Would help if you gave us better quality photos that can be enlarged so we could see the labels and wiring.

-Hal

 

[Seven-Delta-FortyOne]

Site won’t let me load full size pics. I’ll try this one.

The original contactor just had the 3 phase input, the 3 phase output, a 2 wire control circuit from the relay, which is fed from the digital timer, and oddly, a neutral wire connected to the bottom.

I cannot see any info on the relay indicating its voltage, but when the timer activated I have no voltage on the relay output.

The only info I can find on the ABB contactor is one site had a spec sheet showing an input voltage of 24-60 VAC, or 20-60 VDC.

 

[Seven-Delta-FortyOne]

 

[Genepires]

I am wondering if the original remote control switch generated the voltage for the control and then wired down to a dry contact on the intermatic timer. then the signal back energizes its coil to close. that may explain the neutral wire.
the new contactor won't act that way. it is just waiting for coil voltage to operate. maybe that low DC voltage you measured was just some wierd ghost voltage or something magical.

 

[ELA]

Looks like the neutral was removed could that be part of it?

 

[Genepires]

looking closer that white wire is not a neutral? is it connected to "line" on the old contactor?
from a thousand miles away it looks like it is sourcing a voltage that then goes down to the timer and a couple dry contacts create either "open" or "close" on remote control switch? Once again, the new contactor wont operate this way.

we actually need to open up the timer control to see what is going on in there.

also those three pointy end screws that are poking in the cabinet are freaking me out.

 

[curt swartz]

Th original is a mechanically held contactor. Its gets a momentary pules to close and a momentary pulse to close. The control voltage is listed at 110-277V.

The second contactor looks like its magnetically held. I only see the open and close wires going to it, no neutral.

 

[Strathead]

Th original is a mechanically held contactor. Its gets a momentary pules to close and a momentary pulse to close. The control voltage is listed at 110-277V.

The second contactor looks like its magnetically held. I only see the open and close wires going to it, no neutral.

That is what I saw immediately also.

 

[curt swartz]

My post should have said pule to close and pulse to open. Oops.

 

[jim dungar]

Every RCS I remember was mechanically held, usually to prevent the hum associated with the contactor coil.

 

[Master Nater]

there we go. mechanically-held contactor with dual inputs. not just a single, like your new contactor.

better pictures make everything all better.

 

[Seven-Delta-FortyOne]

So what is supplying the pulse? It’s just a standard Intermatic digital timer, connected to a LV relay.

The system is pretty simple: I have 3 phase input off an MCB, 3 phase output to a backfed breaker in a panel with all the lighting, and a digital timer.

I *should* be able to just place a contactor in the circuit, and control it with a timer. Regardless of what was there before. Why not?