Help with a Magnetic Starter for air compressor


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Old 11-19-07, 12:27 PM
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Help with a Magnetic Starter for air compressor

Ok, so with everyone's help i was able to get my wiring completed and ran to the air compressor. Ran the two hot legs to the magnetic starter posts, turned the breaker and disconnect swithc on, and nothing happened. Using a voltmeter, i have 248V across the power terminals on the magnetic starter. This means that my wiring was a success, now I need to figure out this hiccup. Turning the switch on at the magnetic starter, i don't get any kind of sound (no hum, no clicks). As mentioned, volts across the L1 and L3 terminal but no volts across the T1 and T3 terminal (heaters).

I'm hoping it is something super easy that i'm overlooking. Below is a picture of my magnetic starter box. My air compressor's manual says to hook the power legs up to the L1 and L2 posts, which happen to be the left and middle post. I assume this is an error, because the heaters are on the L1 and L3 post. Am i correct in saying that the legs should be attached to the L1 and L3 post? Dumbfounded why this won't start up. If anyone has any ideas, let me know please!

 
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Old 11-19-07, 12:59 PM
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You probably don't have the contactor coil wired into the circuit properly. It is usually controlled/cycled by the pressure switch. The coil looks to be 120V in your picture, so don't wire the control circuit for 240!

Looks like you compressor leads are wired to the the 2 heater overload legs properly.
 
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Old 11-19-07, 01:01 PM
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Originally Posted by formula View Post
The coil looks to be 120V in your picture, so don't wire the control circuit for 240!
Care to elaborate on this? Yes the sticker on the coil says 120VAC. Other than a replacement heater and my ground, red, and black power wire the box is untouched from the factory. The compressor motor itself is a 220V single phase. Are you saying i need to wire from the breaker box to this magnetic starter box as 120V? Does it do the conversion? Now i'm confused LOL
 
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Old 11-19-07, 01:16 PM
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Are you saying i need to wire from the breaker box to this magnetic starter box as 120V?
yes. Your control circuit is probably seperate from the power circuit

Does it do the conversion?
????

what is the wiring coming ion on the left in the wire loom wrap (not legal conduit)??
 
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Old 11-19-07, 01:21 PM
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The wire in the black plastic loom is the low-oil shutoff switch. This was a factory option on the "deluxe" models.

So the magnetic starter requires 120V input, for which it somehow (beyond my knowledge) sends 220V to the motor for it to run? Crap......

This means i'll have to get a single pole breaker and hook it up in 120V then.
 
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Old 11-19-07, 01:23 PM
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there are few issue have to deal with this magantic switch but right now i have few unaswered question what is the very small wire that termated on L2 and T2 ?? what that is used for ??


second thing that did you get this magatinc switch used ?? the reason why i feel quriked but dont get me wrong the magatanic switch itself is from Allen-Bradely but the heater unit itself is from SqD i can tell by shape.


the other reason why the compressor wont start because one common mistake is the O/L heater concat is not hook up at all i dont see any wire on that part


but as soon i find the connection digram i will post it here you will get the idea how it will work in safe manner

Merci , Marc

just tell us what size motor the air compressor itself the line voltage and amparge then we can tell ya the correct way to do this
 
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Old 11-19-07, 01:29 PM
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From what i can tell, the bottom wire on T2 (black wire) and the white wire on the L2 is from the low oil disconnect switch. How this disconnects the system is beyond me. There is also a red wire behind the white one on the L2, which goes down to a terminal block near the bottom of the box, which then goes to the On/Off switch on the side of the box. I'll try to get some better pictures when i get home in a few hours (if you need them).

This magnetic starter is factory installed by American IMC Bel-Aire. The previous owner said he replaced one of the heaters, as it went bad on him. The previous owner said it was working perfectly in his shop. He retired and closed his shop up. This compressor is only 2 years old.

Might have to clarify the O/L heater wire thing. I'm a newb to these magnetic starters
 
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Old 11-19-07, 01:35 PM
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The enclosure is definitely a Square D by looking at the box cover. It has a sticker on the inside of the lid, but i can't read the darn thing. Probably would have made hooking this beast up much easier, but alas i couldn't read it. All i could see is a faint diagram for single and three phase hookup.

Sorry for not mentioning this before, but here is my previous post for running the wire for the compressor. The compressor model is a 318VLE, with a 7.5hp single phase motor with FLA 32A.

Spec Sheet: http://www.abacamerican.com/318VLE%2...high%20res.pdf
 
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Old 11-19-07, 01:55 PM
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Originally Posted by jbuening View Post
The previous owner said he replaced one of the heaters, as it went bad on him.
just so yo know, there is only one heater installed. The part on L3 is a jumper used in place of a heater. Typically not used unless you are running a neutral through the contactor.(as in 120 volt appliance)

and yes, that is very odd that you have a square D box and overload unit but a A-B contactor. very odd.

your on/off switch; is it simply on and off or is it hand (or manual), off, and auto (or something similar)
 
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Old 11-19-07, 02:00 PM
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Just want to say thanks for the help so far everyone.

Ok, so the unit on the left is a heater (has a gear mechanism behind it) and the other is basically a jumper to keep the circuit complete? At least i know where the neutral wire goes now

Not sure what's up with the mismatch of parts. I tried contacting the tech department at IMC but the tech guy has the week off for Thanksgiving. I'll ask him about the mismatch when he returns on monday.

The switch on the side just says On and Off. Turn to the left for OFF and to the right for ON.
 
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Old 11-19-07, 02:01 PM
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when you go looking for things later, you need to find:

the terminals on the contactor coil (may be labeled A1 and A2)

2 or 3 terminals on the side of the overload block. May be labeled C, NC, NO or no labeling at all.
 
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Old 11-19-07, 02:16 PM
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Originally Posted by nap View Post
when you go looking for things later, you need to find:

the terminals on the contactor coil (may be labeled A1 and A2)

2 or 3 terminals on the side of the overload block. May be labeled C, NC, NO or no labeling at all.
What purpose do the A1 and A2 serve, so i kinda know where to look?

Overload block is the unit below the heaters i assume? I'll look for those terminals.


For my own edification, if this were a 240V single phase starter, there would be a heater on both sides with two hot legs going to each L1 and L3? If it were three phase, all three slots would have heaters with three hot legs on the L1-3?
 
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Old 11-19-07, 02:28 PM
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the A1 and A2 are the terminals used to energize the coil that pulls in the contactor that allows the current to flow so the motor will run so you will have air pressure so you can use your impact gun so you can get the tire off your car so you can get it fixed so you can drive the car again so you can get to work so you can earn money so you can ....


are you ready?


are you sure?




buy your dear wife some flowers so she will not be po'd at you anymore for buying the dang air compressor that needed so much work to make it work.


Now, wouldn;t it have been easier to just not buy the air compressor and maybe get some flowers for your wife anyway??

anyway, the overload block is the unit the heaters are attached to.

The terminals are usually on the side way back where you couldn;t get to them without being a little tiny guy with little tiny hands.

Oh, and the A1 and A2 terminals; not sure but it looks like they may be right there on top one being just to the left of L1 and just to the right of L3. Not sure though.

and yes, if it were 3 phase there would be 3 heaters and 240 single phase should have 2 heaters although there are some odd configurations out there, especially when one is designed for single or 3 phase.
 
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Old 11-19-07, 02:35 PM
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Originally Posted by nap View Post

Now, wouldn;t it have been easier to just not buy the air compressor and maybe get some flowers for your wife anyway??
She gets plenty of flowers, i make sure of that. The compressor was 1/3 of the price a new one was, so even if i have to buy a new magnetic starter i'm still money ahead. Got tired of waiting on my little 20 gallon Montgomery Ward (baby crap green circa 1975) air compressor to catch up after a 30 seconds of sandblasting.

Thanks for dumbing things down. I found this diagram just a few minutes ago. Not exactly the same, but gives me a better idea of how this bad boy operates. Looks like mine would be similar to the one on Page 10. It looks like there is 120V going to the motor, so the power circuit must be under the large enclosure on top of the electric motor? This is a first for me seeing 120V input for a 240V motor, but then again I'm not an electrician (news flash! LOL). My old compressor is 240V, but it doesn't have a magnetic starter
 
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Old 11-19-07, 02:41 PM
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Ok, here is the the simplest method to run your control wires.

One caveat; be sure the oil level switch is designed for 120 volt and has enclosed terminals.

remove all wires except for the line and load for the motor.

Then, run a neutral to the A2 terminal of the coil.
(that was the easy part)

Now, run the hot (the one that goes with the neut) to the on/off switch. Then, from the other terminal on that switch to the C on the overload block. Then from the NC terminal (if there is a n/c and n/o terminal) run it out to the oil level switch. then from the other terminal of the oil level switch, run to the air pressure switch (C) then from the NC contact of that switch, back to A2 on the starter coil.

what that all will do is

1. on/off controls all power to the control circuit

2. overload; if tripped, power goes no further so motor will not run or if it overloads and trips out, the motor will stop.

3. oil level; if the oil is low, the switch will not make so the compressor motor will not run. Oil drops while running, the motor stops.

4. pressure switch; if it calls for pressure, and all else is good, the motor runs and when the pressure switch opens, the motor stops.



So, where the heck are all the ground wires that should be in that ground lug???

btw' square D heaters rarely go bad. If the heater wore out, it had tripped too many times so when you get this thing running, you need to take a current draw measurement.
 
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Old 11-19-07, 02:48 PM
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Cool, i'll take a while and try to digest that info

Ground wire from the breaker box and disconnect switch on the garage wall is connected on that ground plug to the left of the contactor (attached to the back wall of the box). Only ground that i know of that needs connected, unless you have others. I think, assuming the PO is honest (could be a mistake), the main problem is me trying to run 240V through a 120V coil. If I rewire the breaker box to 120V, I'm crossing my fingers that this works. I won't be doing any more wiring until i hear back from the manufacturer on whether this 120V coil is original and correct for this compressor. Knowing my luck the PO fried the contactor so he put in a different one, but put in the wrong one as 120V and decided to sell cause it no longer worked. I have that kind of luck

I'll definitely be tracing the wires according to your description to make sure it is ran that way you describe. Thanks for the help, i really appreciate it! Now i know why I'm a structural engineer and not an electrical engineer!

Determining current draw, hmm sounds like my $10 digital voltmeter isn't up to that task What is a common cause for it to trip too many times? Faulty motor, bad wiring, too much cycling? Just curious
 
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Old 11-19-07, 03:31 PM
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Ok, just got home and inspected the box. Here is a short summary of where each wire is going. Maybe this clears things up a bit? I couldn't determine which terminal was the A1 and A2, as they are not marked. The terminals on the side of the overload block are labeled OL and COM. Here is where each wire goes:

White wire from pressure switch -------> L 1/1 terminal

Red wire from A1 (terminal on left above L terminals) ----> L 2/3 terminal

White wire from low-oil switch ------> L 2/3 terminal

Blue wire from switch -----> L 3/5 terminal

Black wire from pressure switch -----> A2 (terminal on right above L terminals)



T 1/2 has no wire attached, other than the heater shown in picture

Black wire from low-oil switch ----> T 2/4 terminal

Red wire from OL terminal (in clear box attached to overload block on lower left backside) -----> T 2/4

T 3/6 has nothing attached other than jumper heater

The posts below the heater and bypass are obviously the output to the motor.

Only other wire left is a red wire from the ON/OFF switch that goes to the COM terminal. The COM terminal is directly behind the OL terminal.

Throw in the input power wires and ground wire and you have everything shown in that picture.
 
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Old 11-19-07, 03:32 PM
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Only ground that i know of that needs connected, unless you have others.
ground from the compressor

ground to the oil level switch

most any circuit needs a ground with it. If it is in metal conduit, the conduit will be considered a ground in many situations although not all. If the conduit is non-metallic, there should be aground along with the circuit.

I think, assuming the PO is honest (could be a mistake), the main problem is me trying to run 240V through a 120V coil
No, you do not run 240 through a 120 volta coil. The 120 volt part controls the 240 volts that passes through the contactor.

. If I rewire the breaker box to 120V,
You need a 120 volt circuit connected as I posted and only as such. The 240 still connect to L! and L# and the moter to T1 and T3. The 240 merely passes through the contactor. That is all the 240 does within the motor starter.

until i hear back from the manufacturer on whether this 120V coil is original and correct for this compressor
really makes no difference. Very simply, I use control voltage based upon what I have available. It has nothing to do with the controlled voltage other than if they are the same, I can steal power from the controlled circuit to power my control circuit. I often have seperate control and controolled power, especially when I am running a 480 volt motor.

. Knowing my luck the PO fried the contactor so he put in a different one, but put in the wrong one as 120V
hopefully he did not smoke the 120 volt coil in the contactor. Continuity tester?? A1 to A2 should have continuity but very low actual resistance.




What is a common cause for it to trip too many times? Faulty motor, bad wiring, too much cycling? Just curious
any and all of the above and add too small of motor, high ambient temp, dirty motor (no air flow for cooling), too small of wire (causing heating which causes resistance which causes more heating which....well, you probably get it)
 
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Old 11-19-07, 04:00 PM
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Without me sounding like a complete idiot, are you saying that i need a 120V source from the breaker box as well as a 240V source? You mention 240V lines still going to the L1 and L3 as i have shown, and then 120V to??? Neutral to A2 and positive to the On/Off switch?? I prefer not to rewire the entire starter box if this is how the factory intended it.
 
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Old 11-19-07, 04:01 PM
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here is one of my digram i used pretty often but for single phase just dont use one line here it is http://www.tpub.com/content/compress...85-13_30_1.jpg

just click on that and it will show the common way to hook up properly and with your low oil cut off circuit wire that in series with pressure switch the reason why i say that if the low oil switch cut out then it will shut the comppressor down

it kinda pretty straght foward job on this one

Merci, Marc
 
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Old 11-19-07, 04:18 PM
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I'm still confused on where this 120V power source is supposed to come into play. That diagram you posted only has 3 hot legs as input and nothing else.
 
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Old 11-19-07, 04:43 PM
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k, so i took my wire descriptions from above and drew them into a diagram to reflect the diagram french posted. It appears from his diagram, that the V (left side of coil) is the A1 and the W is the A2 terminal? Only other thing i'm not sure of is the 2 connection off of the V. Is this the aforementioned 120V source needed to power the coil?

Assuming V=A1 and W=A2, here are my results from my diagram:

The wire from pressure switch to L1 is exactly as the diagram.Where things get tricky is their use of the L2/T2 block. It appears they are using each as a splice/junction point. This is the circuit wired as i see it: A1 goes to L2 junction, then to oil switch, then from oil switch to T2 junction, then to OL, to reset switch, from other post of reset switch to L3. One large series circuit.

So if the oil switch is open circuit, A1 will not have continuity to L3. If the pressure switch is open, then A2 will not have continuity to L1. So this tells me that either my oil pressure switch is open, pressure switch is open, Overload switch is open, or On/Off switch is bad. That is assuming the heaters are still good.
 
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Old 11-19-07, 04:45 PM
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Ok,, you should read my last statement i say you follow the chart i provide but just ingorge one of the 3 phase line connection.

but the other thing it may overlook one thing about coil i know if the label on the cover say 120 volts but really what you can do is take the two screw and unscrew the cover but watchout the springs once you get the cover off you should able see the coil it will genrally marked it clear on that part.

if you dont want to take the cover off then go with diffrent route

if you have netural wire there that great take a one of the hot lead from L1 and wired in series with the O/L , LOCO [ low oil cutoff ] in series of the switch per digram as long the switch you have is on and off but if you have " automatic off hand " stop right there i will or other guys will expain the safe way to do this.

Merci, Marc
 
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Old 11-19-07, 04:52 PM
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I guess i didn't explain it too well. Yeah i saw the comment to ignore the third wire and I did (the L2 post was ignored to reflect my setup). It was mentioned that the coil needed a 120V source, which is where my confusion lies.

So by removing the coil cover, it will be marked as to what voltage it requires?

Also, i don't have a neutral wire. Should i run one to the starter box? If you could, read my previous reply on me following the diagram and how mine is wired. The ON/OFF switch, OL relay, and LOCO is wired in series and with terminals at A1 and L3. Pressure switch is in series terminals A2 and L1. Something i noticed and not sure if it matters, the diagram french posted has the On/Off and pressure switch in series from the A1 to L1 terminal. Mine has the On/Off switch in series with the OL and LOCO, but with A1 and L3 as terminal ends. The pressure switch is on it's own series circuit but has L1 and A2 as terminal ends. I assume my assumption of the left being A1 was incorrect, as if it were A2 it would match the diagram with exception to the On/Off switch being in a different circuit.
 
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Old 11-19-07, 05:01 PM
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In that diagram L2 is neutral.
 
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Old 11-19-07, 05:18 PM
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Originally Posted by fubar2578 View Post
In that diagram L2 is neutral.
Isn't that the third leg of a 3-phase system?
 
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Old 11-19-07, 06:16 PM
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Marc, you've got the guy all confused, or maybe I do. The diagram you posted is for either a 208 or 240 volt coil on the starter. It is using 2 legs of the line side of the motor power.

In marc's (french277) diagram, there is NO neutral. There are only hots.

if I am using 120 volt control on anything other than 120 volt motor, I prefer to have a totally seperate circuit (hot and neutral) for the control. It is easier to isolate the 2 parts.

In my connection listed above you need from the panel

1 hot and a 1 neutral to run the control part of the system

you also need- your 2 legs (that makes your 240) for your motor. The ONLY place the 240 is landed is L1 and L3 and resultingly T1 and T3. there are no other wires connected to L1, L2, or L3.
T1, T2, or T3 (other than the outgoing 240 to the motor)
 
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Old 11-19-07, 10:28 PM
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Originally Posted by nap View Post
Marc, you've got the guy all confused, or maybe I do. The diagram you posted is for either a 208 or 240 volt coil on the starter. It is using 2 legs of the line side of the motor power.

In marc's (french277) diagram, there is NO neutral. There are only hots.

if I am using 120 volt control on anything other than 120 volt motor, I prefer to have a totally seperate circuit (hot and neutral) for the control. It is easier to isolate the 2 parts.

In my connection listed above you need from the panel

1 hot and a 1 neutral to run the control part of the system

you also need- your 2 legs (that makes your 240) for your motor. The ONLY place the 240 is landed is L1 and L3 and resultingly T1 and T3. there are no other wires connected to L1, L2, or L3.
T1, T2, or T3 (other than the outgoing 240 to the motor)

Nap: that diagram i provide that with L-L voltage coil [ either 240 or 480 v depending on the system voltage ]
but if you want the 120 volts for the 120 v coil there is other way you can do is either bring in 120 v circuit or put in transformer to down step from 240 to 120 v to run the coil as well.

to order do that just take the two leads off from the L1 and L2 remove that and hook up 120 v soruce from there.

and it will work this way.

merci, marc
 
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Old 11-20-07, 05:29 AM
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Originally Posted by french277V View Post

to order do that just take the two leads off from the L1 and L2 remove that and hook up 120 v soruce from there.

and it will work this way.

merci, marc

And where does the 240V input from the breaker box go????? The leads on the L1 and I assume you meant L3 are the 240V input. I see no other location to put these at and it has been stated that the contactor NEEDS 240V.

From what i've gathered from this post, the power circuit is the 240V coming in which goes across the contactor and then through the heaters and out to the motor. It's been stated that the power circuit needs 240V

The control circuit is the loop from A1 to L1 and from A2 to L3. It's been stated that the control circuit needs 120V. Each loop is attached to one power leg at an L post. Wouldn't this deliver 120V to the control loop??? Two separate loops with one leg of the 240V?
 
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Old 11-20-07, 05:41 AM
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Originally Posted by nap View Post
Marc, you've got the guy all confused, or maybe I do. The diagram you posted is for either a 208 or 240 volt coil on the starter. It is using 2 legs of the line side of the motor power.

In marc's (french277) diagram, there is NO neutral. There are only hots.

if I am using 120 volt control on anything other than 120 volt motor, I prefer to have a totally seperate circuit (hot and neutral) for the control. It is easier to isolate the 2 parts.

In my connection listed above you need from the panel

1 hot and a 1 neutral to run the control part of the system

you also need- your 2 legs (that makes your 240) for your motor. The ONLY place the 240 is landed is L1 and L3 and resultingly T1 and T3. there are no other wires connected to L1, L2, or L3.
T1, T2, or T3 (other than the outgoing 240 to the motor)
Sorry nap, missed your post before i replied to Marc.

I just don't understand why i have to rewire the darn thing if this is how the factory did it.

So 1 hot and 1 neutral to run the control part of the system and that need to be a totally separate source from the 240V? Does it appear that the factory did not separate them and this is where the wiring conflicts with your advice?

Did you happen to read my reply that stated the wires connected to the L2 and T2 are simply junction terminals instead of splicing/soldering the wires together to form the cutoff circuit? That is the only purpose they are serving.

Yeah i'm really confused, because the manual states to just put the hot legs on the two L posts and that is it. The owner stated that all he removed were two power wires and he pointed at the L1 and L3 posts. So those two stories match, which makes me concerned about rewiring this entire box.

Without completely rewiring all of the connections, is there a spot where the hot and neutral leg need to go? From my last reply, i mentioned the two shutoff circuits. One from A1 through On/off switch through Overload Relay and finally through the LOCO and then terminating at L3. The other goes through the pressure switch from A2 to L1. Again my assumptions of the left being A1 could be wrong. Can you confirm that these two circuits ARE the control circuit? I'll go in baby steps until i understand this darn thing.
 
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Old 11-20-07, 06:22 AM
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Not sure if this will clarify any confusion on your guy's side about how this beast is wired, but here is my diagram of my magnetic starter. Incoming 240V wires are the two coming from the top onto the L1 and L3 terminals. On/off switch and pressure switch are to the right, obviously. As asked before, are the A1 and A2 terminals separate all the time, or do the close at some point? This would alleviate some of my confusion of the 120V control loop.

 
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Old 11-20-07, 08:11 AM
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Have you verified the required voltage for the coil?
The way it is wired now is will work IF the coil is 240. The one thing I see with the way it is wired now is that once the starter engages it bypasses the low oil cutout switch..this may be due to oil splash within the compressor.
 
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Old 11-20-07, 08:32 AM
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The sticker on the front of the contactor reads "COIL 120 VAC 50/60 HZ"

Not sure if there is any other way to make sure the sticker is correct. Is there any crazy way that there could be a transformer or whatever behind the cover of the contactor? Only possible solution is the guy replaced the 240V coil with a 120V coil and wired it up like the 240V coil, couldn't get it to work so he decided to sell it. I'll know more once i hear from the manufacturer next Monday on whether this coil/contactor is original or not.

The low oil switch is in series with the ON/OFF switch, so wouldn't the motor turn off if the low oil switch contacts break (thus opening the circuit)?
 
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Old 11-20-07, 08:54 AM
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Remove the coil cover and read what the specifications are on the coil itself.

I suspect the starter was replaced with an allen bradley as the enclosure is a square d and also the overload relay is a square d. From looking at the picture of the compressor that you gave us a link to, the on/off switch isn't original either(thats an A/B too).

"The low oil switch is in series with the ON/OFF switch, so wouldn't the motor turn off if the low oil switch contacts break (thus opening the circuit)?"

It would only keep the motor from starting due to low oil, once the compressor starts L2 and T2 contacts in the starter are closed and the low oil level switch is bypassed.
(Unless the contacts were removed within the starter)
 
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Old 11-20-07, 09:01 AM
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Not the expert and haven't read all the replies but may I jump in with a suggestion from when I did 480V work. Often the relays (contactors) were 120V. In those cases a small 120V auxiliary transformer was used. If he doesn't have a neutral run that might be the simplest solution. (For testing purposes or temporary operation when there was a bad auxiliary transformer I have actually used an extension ,cord plugged into a 120v line. Got an overhead crane working that way just to finish a rush job while waiting for a new aux Xmer.)
 
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Old 11-20-07, 09:05 AM
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Thanks for the help fellas.

Fubar, what you say makes sense now. The link i provided is the new model, but it is probable that a switch was added. Since the switch is in the same circuit as the low oil switch, i assume that turning the switch to the off position won't turn off the motor once it's running? Interesting....

ray, where are these auxiliary transformers normally located? This may clarify any confusion that may lie if there is one somewhere. Hypothetically speaking, if i were to run a neutral wire where would it go? I assume it would require some re-wiring of the current setup then?
 
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Old 11-20-07, 09:27 AM
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Ray, you're right I've used auxiliary transformers for this as well, I didn't suggest it here because I don't think there is enough room in the enclosure.

Jbuening turning the "on/off" switch off will turn the compressor off only the oil switch is bypassed.

And yes if you go the 120 route the circuit will need some rewiring.

Imo if the coil is only 120 it would be easier and possibly cheaper to buy a 220 coil.
 
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Old 11-20-07, 09:34 AM
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Ok, making more sense now. Isn't the low oil switch in the same series circuit as the on/off switch though?

I'll wait to hear back from the manufacturer first, then i'll be looking at a new 240V coil. Such my luck I assume you can buy just the coil/contactor since this one is a different brand than the heater assembly. From what i've found online (charts), it appears I will need a Type 2 coil/contactor? Are these available from Lowe's/Menards or where is the cheapest place to get them? Thanks for the help everyone, sorry for all of my confusion. I've learned alot about these with this thread
 
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Old 11-20-07, 09:48 AM
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The low oil switch, overload contact and the switch are on the same part of the circuit,however when the starter engages L2 and T2 are connected by the contacts in the starter. Since the oil switch is connected to L2 by one wire and T2 by the other wire the oil switch alone is bypassed the rest of the circuit functions as normal.

No you won't find the coil at the any of the big box stores.
Take the numbers from the starter to a local electrical supply and let them get you the correct coil.
 
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Old 11-20-07, 01:07 PM
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One more question, the upper piece is a combination of the coil and contactor correct? The coil is underneath the contactor box? So if i am getting all of this straight, i just need to get a 240V coil and leave the wiring the same on the contactor box?? I assume that when i remove the contactor box, i'll see something "similar" to this (which is what needs replaced):




I'm wondering if the original contactor/coil assembly looked similar to this:



http://cgi.ebay.com/SQUARE-D-1-PHASE...QQcmdZViewItem
 
 

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