Electrical for shop

Al killian

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Floydada, Tx
Not sure where this goes, so if need please move. OK, My temp shop has what should be 150 amps of power. It is split off the pole, one led going to the house and one going to the barn. There is a 200 amp service in the house and a 150 amp in the barn. Main line is rated for 200 amps. Now the big thing is My molder pulls 35 amps on average(unless in a hurry:D). The feed motor draws 5 amps. His panel is somewhere around 30 plus old. The weird thing is I am running 8 guage wire(pulled from last shop) 25' to the machine. When fireing it up it takes over 30 seconds for it to reach full speed/power. It is on a 50 breaker(orginal to the panel). The motor will actually stop turning, but not tripp the breaker. Could this be a problem with the panel and/or breaker? I had the sme setup in my other shop and never had a problem. If need be I have a 200 amp panel to switch out if need be. Yes I am very knowledgeable about electricity. Just stump by this.
 
Al have you checked that all the screw joints on the breakers are tight. Seems to me you getting a voltage drop that get worse when you draw current. I have experienced this way back when in the army and it was a loose breaker connection. By loose i dont mean really sorta hanging loose. But not tight enough and not enough of the copper in the line under the screw making contact. When you draw that kinda current contact resistance will cause a volt drop and it can be significant.

Get the meter and measure the voltage at the various stages. Do you have someone that can man the breaker while you do this in short bursts to find the problem.

Pictures of the panel would also be a help. You say old how old. Was the panel ever subjected to this kinda load before.


Just had some more thoughts and questions. Is your moulder single phase or three phase. What feeds the panel. Could be one of the phases that feeds the panel is out right from the pole.
 
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AS other have said I would suspect the breaker. Either not tight of some oxidation on the contacts. Assuming it 220, with a volt meter check each leg to ground under no load then while someone start the machine check each leg. If there is little or no differance and not a signifcant drop then check it at the machine.
 
One thing you said bothers me: "It is split off the pole, one led going to the house and one going to the barn. There is a 200 amp service in the house and a 150 amp in the barn."

Do you mean there's only one WIRE from the pole to the barn? If that's the case, you only have 120V~ service, which would explain why the molder runs up slowly (I'd be surprised that it'd run up at all.).
 
Yeah, I saw that in the original post, also, and wondered. You need both poles going to the shop (as well as the house if you need 240V there) in order to get the 240. The two hots got to be on opposite sides of the cycle to get the voltage drop you need.
 
One thing you said bothers me: "It is split off the pole, one led going to the house and one going to the barn. There is a 200 amp service in the house and a 150 amp in the barn."

Do you mean there's only one WIRE from the pole to the barn? If that's the case, you only have 120V~ service, which would explain why the molder runs up slowly (I'd be surprised that it'd run up at all.).

By split, I mean it come as on line to the pole and the it is split into two service.

Yes it is 220 volts single phase

Been happen since I took over the barn

Panel is a old Culter Hammer(tan) breaker setup.

Been thinking of trying a new breaker as I just looked and it seems to have some rust on the contacts of the breaker

Yes The contacts are tigth. Just went thru are rechecked. Even added some contact gease.

Haven a sparky freind drop by on monday to do a load test and check the legs for me.
 
Very good idea!! "Haven a sparky freind drop by on monday to do a load test and check the legs for me."

May save you some $$$$ for motor replacement.... and you will feel safer!!

paul
 
Just a thought.....If the motor is 40 amps and you have a 150 amp service. Maybe with the initial surge when turning on the machine it could draw over 80 amps for a few seconds. With any other machines, heat, lights on you may not have enough power. Have you tried running the machine without anything else on?
 
Just a thought.....If the motor is 40 amps and you have a 150 amp service. Maybe with the initial surge when turning on the machine it could draw over 80 amps for a few seconds. With any other machines, heat, lights on you may not have enough power. Have you tried running the machine without anything else on?

Nope.:D Will tommrow.
 
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