combo disconnect /motor starter

[bennie]

Re: combo disconnect /motor starter

Magnetic starters are wired for any control voltage. The only problem with 120 is switching the grounded conductor (if it is grounded), this does not present a hazard, nothing is energized that is not intended to be.

I would not want to be the inspector that called for rewiring the starter.

Both wires to the coil will often be the same color, usually black. This is when 240 and 480 control voltage is used. There is no issue for which side the overload switches are located.

 

[ronaldrc]

Re: combo disconnect /motor starter

Bennie I agree with you on that.I'm not talking about the overload switches,I'm talking about the switch that starts the motor be it momentary push buttons or a maintain contact like a toggle switch. If there is nothing on the hot side of the coil to open the coil circuit and the neutral faults to ground as it leaves the coil before it gets to the starting switch then the coil will be energized and the motor will run.

If the neutral and ground are bonded.

Ronald

 

[bennie]

Re: combo disconnect /motor starter

Hello Ronald: I haven't mentioned that you have been missed, where you been?

As Don stated; an accidental fault on the neutral, before the overload switches will
defeat the function of the switches.

The only way a mag starter can self start when not intended, is when the start or holding contacts are welded or shunted.

 

[roger]

Re: combo disconnect /motor starter

Bennie wrote,

Hello Ronald: I haven't mentioned that you have been missed, where you been?

I'll second that.

Roger

 

[ronaldrc]

Re: combo disconnect /motor starter

Hi Roger good to hear from you.

I know you missed me a lot Ha.

Come on now I think Bennie is just giving me a hard time as usual, your a control man if you had your starting switch for a magnetic starter in the common side 120 coil and a grounded neutral and the common shorted to ground the motor would run.

Really the overload contacts wouldn't play apart in a control circuit fault anyway they open under motor load.

Ronald

 

[bennie]

Re: combo disconnect /motor starter

OK Ronald, post a drawing of a motor starter control circuit, with a stop and start station.

You will answer your own question.

 

[ronaldrc]

Re: combo disconnect /motor starter

You all are a lot of trouble I got to do this to show everybody else.

Ronald

 

[ronaldrc]

Re: combo disconnect /motor starter

Originally posted by ronaldrc:
You all are a lot of trouble I got to do this to show everybody else.

I'm finished

Ronald

 

[ronaldrc]

Re: combo disconnect /motor starter

Sorry about the double post I keep hitting the wrong icon to edit. I wish one of the moderators would remove the first picture.

Does any one reading this no anything about computers, for some reason I lost my address bar I reloaded Internet explorer and its still not there. Help

Ronald

 

[bennie]

Re: combo disconnect /motor starter

Ronald: The start and stop switches are never on the ground side, only the overload switches.

 

[iwire]

Re: combo disconnect /motor starter

Go to "View" to "Toolbars" and make sure "Address Bar" is checked.

You can edit your own post by clicking on this symbol

You can remove or change whatever you want.

Bob

 

[ronaldrc]

Re: combo disconnect /motor starter

I,wire Thanks I checked that and it was ok what it was was I had pushed the address bar up under the rest of the tool bar.

Ok Bennie.

Thanks:Ronald

[ July 12, 2003, 04:58 PM: Message edited by: ronaldrc ]

 

[ronaldrc]

Re: combo disconnect /motor starter

Bennie you know I didn't mean that when I said you are a lot of trouble.I wish I had just half your electrical knowledge.

I had that diagram already drawn and didn't want to post it.But I had to prove my point.

I no your not suppose to put the push buttons in the common side but its done everyday just like the XO to ground case jumper is left off a lot of secondary distribution transformers and know one knows nothing untill one day a line touches the ground and they fry a lot of expensive equipment because the other two line to ground have 208 volts.

Just common mistakes made everyday from not thinking things out.

Thanks:Ronald

 

[bennie]

Re: combo disconnect /motor starter

I'm worried now Ronald, you can predict my next move

I thought that drawing appeared very quick.

Troubleshooting trivia for a mag starter...Problem...Starter wil not close when start switch is pressed.

Close the starter by hand pushing the armature up.

If it seals in, the problem is the start switch.

If it don't seal in, an overload switch is open.

 

[ronaldrc]

Re: combo disconnect /motor starter

Bennie you no thats funny because just after I posted my picture I refreshed my page and your post was there asking me to post a picture of the circuit, scared me I thought you read my mind.

Ronald

 

[bennie]

Re: combo disconnect /motor starter

Do these computers have artificial intelligence?

I'm sitting here watching "Roswell" on the TV.

 

[ronaldrc]

Re: combo disconnect /motor starter

Here is the Art. that covers the violation of putting the start switch in the common or grounded side of the control circuit out of the 2002 NEC.



[ July 16, 2003, 03:25 PM: Message edited by: ronaldrc ]

 

[bennie]

Re: combo disconnect /motor starter

The overload switches are in the grounded side out of necessity.

Start and stop signals are generated on the active side. A grounded wire is installed at the start and stop stations only for the indicator lights if used.

The only area where shorting to ground can be a problem, is the few inches of wire from the coil to the terminal. Downstream from the switches is no problem.

 

[ronaldrc]

Re: combo disconnect /motor starter

Hi Bennie

Although I disagree, if the push buttons are on the common side.It could start the motor anywhere between the coils common terminal all the way untill it gets to the start button.That could be a few inches or could be a hundred feet.

But you bring up a good point why, are the overload contacts always on the common side? I always thought it just makes the circuit simplier and easier to remember.

Is there another reason?

Ronald

 

[bennie]

Re: combo disconnect /motor starter

Ronald: The push buttons are always on the L-1 active side. The OL switches can be on the L-1 or L-2 side.

Control transformers are usually confined to one starter, there is no difference in which side is switched.

Motor controls are not part of the premises wiring system, there is no violation for switching the grounded side. Article 100.