So I was looking at the new motor and up until now I didn't really pay attention to it but the damn thing doesn't have a nameplate (took it out of the box and threw it right up on the compressor tank). I'm thinking I got a refurbished motor that someone forgot to slap a sticker on. The first thing that threw me off was the difference in wire color from the original motor I sent but now that I don't see a nameplate sticker that's the only thing I can think of. The outside of the motor is completely blank other than the warning label. Absolutely no stickers or other markings on this thing??
Compressor Motor Issues
- Thread starter El_Diablo
- Start date
There is no common on a true 5HP 240 VAC motor. There're two hots (L1 and L2 both of which are connected to 240VAC).
Without a diagram it's hard to say what happened. Maybe you managed to miswire the centrifical switch connection which could cause the start cap/winding to overheat.
IMHO you need to be dealing with the supplier to get this straightened out. Maybe they sent you the wrong style motor.
You keep referring to "common" wire. A 230v single phase motor does not have a "common" wire.
You've got a Black lead at rear of motor and a Red lead at rear of motor. One wire from your 230v breaker goes to the male terminal next to the Black. The other wire from your breaker goes to the male terminal next to the Red. Then you take the bare copper ground wire from your breaker box and secure it to the green screw on motor housing. It's as simple as that.
This is a CCW rotation motor only and is not reversible. so, there are no additional wires to deal with.
I think the majority of us would agree you should not be attempting to wire a simplistic motor to a mag starter and pressure switch. I'm in no way trying to be an *** here but am just in fear for your safety and the safety of others. Air compressors are not toys and must be plumbed with properly sized pressure switch, multiple properly sized pop-off safety valves, and wired correctly.
You've got a Black lead at rear of motor and a Red lead at rear of motor. One wire from your 230v breaker goes to the male terminal next to the Black. The other wire from your breaker goes to the male terminal next to the Red. Then you take the bare copper ground wire from your breaker box and secure it to the green screw on motor housing. It's as simple as that.
This is a CCW rotation motor only and is not reversible. so, there are no additional wires to deal with.
I think the majority of us would agree you should not be attempting to wire a simplistic motor to a mag starter and pressure switch. I'm in no way trying to be an *** here but am just in fear for your safety and the safety of others. Air compressors are not toys and must be plumbed with properly sized pressure switch, multiple properly sized pop-off safety valves, and wired correctly.
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Never have seen a motor with the leads marked “L”, “C”, “H”.
But then again it’s just some imported…….
This is just a hunch, but maybe the connections are as follows:
Since your house is supplied with a 120 / 240 volt service the voltage to the motor would be at 240 volts.
The motors rating is 208 / 240 volts
So, maybe the foreign language for this would be:
L = low voltage or 208 volts
C = common
H = high voltage or 240 volts
So the connection would be:
C = Line 1 (one leg of the 240 volt line coming in)
H = Line 2 (the other leg of the 240 volt line coming in)
L = no connection (not used)
Then of course connect the ground.
You stated that the final connection made was red leg connected to the “L” and the black leg moved and re-connected to the “C” when the motor came to life.
Now maybe I’m wrong here, but that could mean you connected to the 208 volt connection, the motor ran for a while then….. well, you know, up in smoke?
Just my theory, but who knows, it’s an import, most likely just junk!
But then again it’s just some imported…….
This is just a hunch, but maybe the connections are as follows:
Since your house is supplied with a 120 / 240 volt service the voltage to the motor would be at 240 volts.
The motors rating is 208 / 240 volts
So, maybe the foreign language for this would be:
L = low voltage or 208 volts
C = common
H = high voltage or 240 volts
So the connection would be:
C = Line 1 (one leg of the 240 volt line coming in)
H = Line 2 (the other leg of the 240 volt line coming in)
L = no connection (not used)
Then of course connect the ground.
You stated that the final connection made was red leg connected to the “L” and the black leg moved and re-connected to the “C” when the motor came to life.
Now maybe I’m wrong here, but that could mean you connected to the 208 volt connection, the motor ran for a while then….. well, you know, up in smoke?
Just my theory, but who knows, it’s an import, most likely just junk!
I keep referring to it because you guys keep telling me the same thing which was my mistake and the reason I had the issue in the first place, lol. The issue has since been corrected and everything was working just fine right up until the capacitor blew.
I called up northern tool and they have stated that my 240v thats going to the motor is to much voltage and thats why the capacitor blew so looks like I'm just going to go with a different motor.
Bottom line, I made a bonehead mistake with the common wire but I know the basics of plumbing and electrical I've just never wired up a 220v component such as this before so I screwed up and attached the common. My bad, I completely accept that but the compressor worked great right up until the capacitor blew.
Oh, and as for the switch, I was going off of the advice from northern that a capacitor motor didn't need a mag starter
. Also, the pop off is actually oversized for the pump that I'm using 
I called up northern tool and they have stated that my 240v thats going to the motor is to much voltage and thats why the capacitor blew so looks like I'm just going to go with a different motor.
Bottom line, I made a bonehead mistake with the common wire but I know the basics of plumbing and electrical I've just never wired up a 220v component such as this before so I screwed up and attached the common. My bad, I completely accept that but the compressor worked great right up until the capacitor blew.
Oh, and as for the switch, I was going off of the advice from northern that a capacitor motor didn't need a mag starter
. Also, the pop off is actually oversized for the pump that I'm using Never have seen a motor with the leads marked “L”, “C”, “H”.
But then again it’s just some imported…….
This is just a hunch, but maybe the connections are as follows:
Since your house is supplied with a 120 / 240 volt service the voltage to the motor would be at 240 volts.
The motors rating is 208 / 240 volts
So, maybe the foreign language for this would be:
L = low voltage or 208 volts
C = common
H = high voltage or 240 volts
So the connection would be:
C = Line 1 (one leg of the 240 volt line coming in)
H = Line 2 (the other leg of the 240 volt line coming in)
L = no connection (not used)
Then of course connect the ground.
You stated that the final connection made was red leg connected to the “L” and the black leg moved and re-connected to the “C” when the motor came to life.
Now maybe I’m wrong here, but that could mean you connected to the 208 volt connection, the motor ran for a while then….. well, you know, up in smoke?
Just my theory, but who knows, it’s an import, most likely just junk!
That's probably the case but oh well, live and learn. This was a learning experience that I won't forget. Just think, all of this could've been avoided with a simple wiring diagram or even just proper labeling
First, Northern tool is full of ****.
All motors are rated with a certain +- voltage variation. No way you blew a capacitor because of that minute amount of over voltage. A standard household circuit typically ranges from 110v to 120v on any given day.
Second....Northern tool is again full of ****.
There is no correlation between a capacitor start motor and a mag starter.
Use of a mag starter is required on a compressor system if (1), the pressure switch contacts are not rated to handle the motor amperage, and (2) if motor does not have thermal overload protection.
Since this motor has thermal overload protection and pressure switch is commercially available to handle the amperage, you are good to go.
The leads from the 230v breaker get wired directly to contacts on the pressure switch. Then another set of leads get wired from contacts on pressure switch directly to the motor. The electrical contacts on the pressure switch itself is responsible for starting/stopping the motor.
All motors are rated with a certain +- voltage variation. No way you blew a capacitor because of that minute amount of over voltage. A standard household circuit typically ranges from 110v to 120v on any given day.
Second....Northern tool is again full of ****.
There is no correlation between a capacitor start motor and a mag starter.
Use of a mag starter is required on a compressor system if (1), the pressure switch contacts are not rated to handle the motor amperage, and (2) if motor does not have thermal overload protection.
Since this motor has thermal overload protection and pressure switch is commercially available to handle the amperage, you are good to go.
The leads from the 230v breaker get wired directly to contacts on the pressure switch. Then another set of leads get wired from contacts on pressure switch directly to the motor. The electrical contacts on the pressure switch itself is responsible for starting/stopping the motor.
brawls43
Well-known member
The big lesson learned should be to not wire a motor without the wiring diagram. The main damage to the capacitor probably happened all those times when blowing the breaker. 220-240V fluctuation in a household circuit is normal.
I agree, like I said, bonehead move and I'm paying for it (litterally).
Agreed about northern.
I actually have an electric plug that will be getting hooked up to the motor in case I ever need to move the compressor back down the flight of stairs!
Thank you guys for all of your help.
Agreed about northern.
I actually have an electric plug that will be getting hooked up to the motor in case I ever need to move the compressor back down the flight of stairs!
Thank you guys for all of your help.
Northern agreed to refund the money on the motor. I went ahead and purchased a 6hp compressor duty motor from Tractor Supply with a 1yr warranty and 3yr service plan for $309 after tax and all that BS. Luckily I found one that the RPM and shaft size both match the motor from Northern. I will probably wire it up tonight or tomorrow.
Sheesh!
If you are spending that much money, buy a Baldor 5HP 1725 RPM motor with NEMA 184 frame. That is a true compressor duty rated motor. The model L1430T or L1410 is a good choice for your application.
Don't expect to achieve a long motor life when you buy a 5HP motor rated at 3450 RPM in a NEMA 56 frame.
If you are spending that much money, buy a Baldor 5HP 1725 RPM motor with NEMA 184 frame. That is a true compressor duty rated motor. The model L1430T or L1410 is a good choice for your application.
Don't expect to achieve a long motor life when you buy a 5HP motor rated at 3450 RPM in a NEMA 56 frame.
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Trey T
Well-known member
^thats like two hundred bucks more with a mag starter
Baldor 5hp motor on eBay: 375$
Magnetic starter on eBay: :$125
Baldor 5hp motor on eBay: 375$
Magnetic starter on eBay: :$125
b-body-bob
Well-known member
The Baldor L1430T (US made) I just bought had no overload protection (didn't need it, have a mag starter) and cost $360 new in an unopened box including shipping, no tax, with a 12 month warranty. The one I bought has a 1-1/8" shaft.
Just look on e-bay you may find a model that will work for you.
There are also NOS "take off" motors (no warranty though) and Leesons (18 mo. warranty but made in Mexico) listed there too.
Just look on e-bay you may find a model that will work for you.
There are also NOS "take off" motors (no warranty though) and Leesons (18 mo. warranty but made in Mexico) listed there too.
kams1973
ALLIANCE MEMBER
The motor from tractor supply will work fine for your application. I've used that motor for a 5hp SB air compressor build.
The motor itself was only $250 but after tax and $40 for the service plan the price went up. I'm not usually one for a service plan but the setup they had is decent since the motor wont be in a clean room. I also like that it was an in person transaction. The online back and fourth to save a little just gets old. All the locals around here wanted over $400 OTD for a decent 5hp motor. I'll eventually step up when this one fails but for now I think it will work for what I need.
it'll work for your application. If you purchased a HF compressor then obviously you're not looking for something to last 20 years and there is nothing wrong with that. Your set up will be a good starter compressor system.
Main thing to be concerned with is to size the motor pulley as to not overload the amperage rating as shown on the motor nameplate. That will be critical to achieving adequate motor life expectancy. Clip on style amp meters are pretty economical and would be a good investment to add to your tool box.
Main thing to be concerned with is to size the motor pulley as to not overload the amperage rating as shown on the motor nameplate. That will be critical to achieving adequate motor life expectancy. Clip on style amp meters are pretty economical and would be a good investment to add to your tool box.
The plan is honestly to run this setup until something dies, upgrade it, run it until the next thing dies, upgrade it and just keep on that cycle until everything is upgraded to brand name, somewhat high end parts. Ideally I would like to add another 80-120 gallon storage tank to this setup in the future.
Just wanted to give an update, the TSC motor is on and works great with no issues. I could tell right away it was a lot beefier. It has a built in junction box with a gasketed cover plate and the wiring is a lot heavier and overall the motor seems to be of higher quality than the northern tool ironton motor. Overall, so far I'm very happy with the purchase.
post some pics for all of us.
Just as a precaution, I'd take amperage rating of each lead to ensure you are not drawing more amperage than what is stated on the name plate. Motor amperage will be highest at the point when compressor cycles off.
If this is the case, you'll need to run a smaller motor pulley to slow the compressor down.
Just as a precaution, I'd take amperage rating of each lead to ensure you are not drawing more amperage than what is stated on the name plate. Motor amperage will be highest at the point when compressor cycles off.
If this is the case, you'll need to run a smaller motor pulley to slow the compressor down.