Electrical problem with a Delta shaper
To All:
I have a Delta 2 hp shaper that has never been used but is about 10 yrs old.
I replaced the original 14/3 cord with a cord approx twice as long. I plug the shaper into a receptacle that I also use to plug in my 3 hp table saw. I don’t run more than one machine at a time so the circuit is dedicated to the machine in use. The receptacle is wired using 12/3 Romex to a 20 amp 220 breaker. The shaper has a magnetic starter. I start the shaper and it runs fine. I shut off the shaper and let it sit for up to an hour. When I restart the shaper, it starts to spin and then kicks the breaker. I have tried shortening the cord to 8′ and it makes no difference. I have never kicked the breaker using the table saw. The problem is consistant in that it will always kick the breaker on the restart. The motor never gets warm. I am not sure what the problem might be. Any ideas?
Thanks
Tony
Replies
Breakers trip when the excess current causes them to heat up until a temperature sensitive element in the breaker is triggered. Even under a normal load a breaker will get warm and become more and more sensitive to an overload and I suspect that this is what is happening in this case. After you have used the shaper and the saw for awhile the breaker will have warmed up and the surge from restarting the shaper would then be enough to cause it to trip.
Breakers that trip often tend to wear out and will then start to trip even when the circuit isn't truly overloaded. My suggestion would be to replace the tripping breaker with a new one of the same size, that will probably solve the problem.
John White
John and all:
I replaced the 20 amp breaker today and it seems to fixed the problem. The breaker is probably 15 years old and had not been tripped much until now but it might have been just enough to trip the old breaker. Thanks for your help. I'm glad it was a $10 fix and not a motor.
Regards,
Tony
Does the shaper trip the breaker when it's just spinning the cutter or just when it's cutting? It shouldn't be pulling many amps when it's unloaded. Since your 3 hp TS doesn't trip the breaker I don't think it's the breaker. I think it's the motor. After sitting around for 10 years there could be a bad capacitor or starting switch or it might be plugged up with spider webs or a loose internal connection. There may even be an intermittent short. Replacing a 20A breaker is easier and cheaper, but I suspect you may end up at a motor shop. Let us know.
John O'Connell - JKO Handcrafted Woodworking
The more things change ...
We trained hard, but it seemed that every time we were beginning to form up into teams, we would be reorganized. I was to learn later in life that we tend to meet any new situation by reorganizing; and a wonderful method it can be for creating the illusion of progress while producing confusion, inefficiency, and demoralization.
Petronious Arbiter, 210 BC
The weight of the drive line on the shaper combined with the drive ratio to give a higher RPM could easily mean that the 2 hp shaper has a higher starting surge than the 3 hp table saw. Surge is also affected by the design of the motor, some motors are better than others. The 14 ga cord could also be causing some extra draw.
John W.
I agree it could be, but I doubt it. For instance I have an old Foley 12" planer with a 5 hp motor and 3 belt drive running on 240V. It's spinning a lot more metal than a L/W Delta 2hp shelter and pulls around 4 amps unloaded. Perhaps the consistent, predictable restart failure of the shaper provides the reason why it's an unused 10 year old shaper!John O'Connell - JKO Handcrafted Woodworking
The more things change ...
We trained hard, but it seemed that every time we were beginning to form up into teams, we would be reorganized. I was to learn later in life that we tend to meet any new situation by reorganizing; and a wonderful method it can be for creating the illusion of progress while producing confusion, inefficiency, and demoralization.
Petronious Arbiter, 210 BC
As I read his description, it's the starting surge on the second start that is causing the problem, it pops the breaker as it is starting up. I hope we find out the cause, it is an odd set of symptoms.
John W.
Yes it is odd for a shaper. perfectly normal for a worn out compressor. Maybe he's confused? :)John O'Connell - JKO Handcrafted Woodworking
The more things change ...
We trained hard, but it seemed that every time we were beginning to form up into teams, we would be reorganized. I was to learn later in life that we tend to meet any new situation by reorganizing; and a wonderful method it can be for creating the illusion of progress while producing confusion, inefficiency, and demoralization.
Petronious Arbiter, 210 BC
My guess is the magnetic starter is not functioning correctly. My buddy, Corky, had a 3-hp motor with a magnetic start that was doing pretty much the same thing, except it was also doing it intermittently on a cold start. Another buddy, Neil, who was an electrician, played around with something on the magnetic starter, and the problem went away.
Hopefully, someone better versed on motors, and the magnetic starters will pitch in soon.
If not, try posting over on Breaktime, the Fine HomeBuilding equivalent of knots, and see if one of the guys over there can help out.
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