Please help with electrical situation

[Walter Stokes]

I received and installed, with the forums help, a G0609 12" jointer and the G1021X 15" planer. In anticipation of my new equipment I had an electrician install 220 volt power to three places in my 3 bay garage. He ran 12 wire and put in 20Amp breakers.
The machines are tuned up and ready to cut wood BUT when I cut one of them on it pops the circuit breaker. I paid $1,185 to have the work done and I have nothing useable. Any electricians out in the forum have any good ideas of what I should do now. Do I need 10 ga. wire and 30 amp breakers? The Grizzly manual on the machines say 12 ga with 20 amp circuit is sufficient. I do know that the panel box is about 50 feet from where the outlets are. Could this be the problem? The electrician who installed the lines will be here in the morning to see what is going on. Did he mess up the first time? Do I just pay to redo the job? Does he have any responsibility? Any guidance is greatly appreciated. If my wife sees another $1185 dollar bill she is gonna flip out.

[S Larkin]

Most reputable electricians stand behind their work. Call yours back to help you determine what's wrong.

[Carl Eyman]

Ask your electrician if a time delay fuse/breaker is the answer. If the breaker is going out right away after you turn the machine on it is the starting load that is killing you. There are several ways to deal with this, but not many of them apply to small motors. Larger motors may require a reduced voltage starter, but these are seldom if ever used on 3 or 5 h.p. motors. If the machine manufacturer says a conventional 20 amp breaker is all you need, then that should be all you need.

Anyway that is my $.02 worth; don't know if you got your money's worth or not.

[Jerry White]

My G1021X planer is on a circuit wired with 12 ga wire and a 20 amp breaker. I have had no problems with tripping the breaker. I use this circuit for only one machine at a time.

This size circuit should also be appropriate for the G0609. Unfortunately, I do not have that one in my shop. I wish I did. :)

Congratulations on two nice pieces of equipment. I'm sure your electrician will figure it out.

[chris del]

Here is a description of your planer from the Grizzly site:

All ball bearing construction with powerful 3 HP, single-phase motor, 18 amp,



The electrical code states that no electrical device should exceed 80% of the rated circuit. So for a 20AMP circuit, you should not run anything over a maximum 16Amps.... It appears you need a 30Amp circuit my friend.

My planer is also a 3hp and about 19amps. I ran a 30Amp circuit for it.

These machines often draw full rated load and maybe a bit more on startup.

[Jason Beam]

I'm with Chris on this one. Always run at 80% capacity or less. That extra 20% is elbow room for bursts of high load. Some motors can draw up to 10 times their rated amperage at startup for a brief moment and this is one of the contributing factors for the invention of the "Slow blow" fuse way back when.

Are you going to be running a dust collector on the same circuit? If so, you'll most certainly need some more juice.

As to if the electrician is responsible, were the amperage specifications provided to him prior to work and was it clear how many amps were being drawn? If so, then yes it's on him.

[Don Bullock]

The first thing I would do would to be to call Grizzly and double check to see if the manuel is correct. I'd also let them know what problems I was having and ask them for possible problems and recommendations.

The electrician who installed the lines should be able to solve the problem for you. It could be just a loose wire or a bad breaker. I'm afraid, however, that Chris may be correct with his electrical calculations. Again, your electrician should know what the equipment needs.

Good luck.

[chris del]

I just did some checking and all the 3600rpm (2 pole) motors that I have seen are rated for 16A or less. So lets say for argument sake that you are borderline for a 20A circuit. I would question the lenght of your 12Ga wire. Too long and you will get voltage drop in the line, therefore requirements at the breaker may peak just enough to trip.

If the motor is a true 18A, I would file a complaint with Grizzly. You are a woodworker not a expert in electrical. Grizzly is responsable for providing the correct information.... In this case, their error could cost you a few more hours with the electrician.

[Rick Christopherson]

The electrical code states that no electrical device should exceed 80% of the rated circuit. So for a 20AMP circuit, you should not run anything over a maximum 16Amps.... It appears you need a 30Amp circuit my friend. Don't state code as a fact when you don't know code. This is a cord and plug application, and the 125% derating is not required. The end user is fully permitted to use all available power from the circuit, and #12 wire is capable of supporting 25 amps.

As for the existing circuits, 3 hp motors should be just fine on a 20 amp circuit. If the breakers are tripping instantly, then it is most likely that either the breakers are not properly rated for motor draw, or the electrician mistakenly wired them at 120 volts at the panel.

If this was happening only periodically or when the tools were in operation under heavy load, then I would suggest the circuits were undersized. However, because this is happening instantly, then it would appear to be a wiring problem. Have your electrician double check the wiring to ensure he is getting 240 volts at the tool, and also confirm the type of breaker used.

P.S. A 50 foot run from the panel to the outlet is not enough to have an appreciable voltage drop, nor is it within the bounds for derating under the NEC.

[chris del]

Don't state code as a fact when you don't know code. This is a cord and plug application, and the 125% derating is not required. The end user is fully permitted to use all available power from the circuit, and #12 wire is capable of supporting 25 amps.

As for the existing circuits, 3 hp motors should be just fine on a 20 amp circuit. If the breakers are tripping instantly, then it is most likely that either the breakers are not properly rated for motor draw, or the electrician mistakenly wired them at 120 volts at the panel.

If this was happening only periodically or when the tools were in operation under heavy load, then I would suggest the circuits were undersized. However, because this is happening instantly, then it would appear to be a wiring problem. Have your electrician double check the wiring to ensure he is getting 240 volts at the tool, and also confirm the type of breaker used.

P.S. A 50 foot run from the panel to the outlet is not enough to have an appreciable voltage drop, nor is it within the bounds for derating under the NEC.

Thanks for putting me in my place Rick. True, I do not know code. I am more like a parrot and I was just repeating what a lisensed electrician told me. I shouldnt even begin to pretend that I know what I am talking about, specially in a different country.
I assume you are a lisensed electrician or electrical engineer. Either way you are clearly more well versed than me when it come to electrical.
I will keep my mouth shut and see how the thread plays out.

Chris

[Cliff Rohrabacher]

Here is a description of your planer from the Grizzly site:

All ball bearing construction with powerful 3 HP, single-phase motor, 18 amp,



The electrical code states that no electrical device should exceed 80% of the rated circuit. So for a 20AMP circuit, you should not run anything over a maximum 16Amps.... It appears you need a 30Amp circuit my friend.

My planer is also a 3hp and about 19amps. I ran a 30Amp circuit for it.

These machines often draw full rated load and maybe a bit more on startup.

What he said.

Convert those 20 amp lines to multi station outlets and lights and install your own #10 gauge and 30 amp breakers.
There is no need to hire any one to run a single line from a single breaker. Just don't do it while the power is on like I do. One day they'll find me deep fried on the shop floor. Too lazy to go flip a main breaker.

[Scot wolf]

12 gauge is good for 25 amps (art. 430). If everything is wired corectly then he could just change out the breakers.

[Alan Tolchinsky]

12 gauge is good for 25 amps (art. 430). If everything is wired corectly then he could just change out the breakers.

I always thought 12 guage wire needs 20 amp circuit breakers for protection. Are you saying to use higher rated circuit breakers? That sounds like unusual advise. Care to explain?

[Rick Christopherson]

I was just repeating what a lisensed electrician told me. I am sorry you are offended, but you stated code as fact and in an authoritative manner. Therefore, other people read this, and assume that you are an authority and the information is correct. This is how misinformation gets started, and with electrical systems, misinformation is not good. If you had said up front that you were just repeating what you heard elsewhere, that would have been different.

[David G Baker]

I received and installed, with the forums help, a G0609 12" jointer and the G1021X 15" planer. In anticipation of my new equipment I had an electrician install 220 volt power to three places in my 3 bay garage. He ran 12 wire and put in 20Amp breakers.
The machines are tuned up and ready to cut wood BUT when I cut one of them on it pops the circuit breaker. I paid $1,185 to have the work done and I have nothing useable. Any electricians out in the forum have any good ideas of what I should do now. Do I need 10 ga. wire and 30 amp breakers? The Grizzly manual on the machines say 12 ga with 20 amp circuit is sufficient. I do know that the panel box is about 50 feet from where the outlets are. Could this be the problem? The electrician who installed the lines will be here in the morning to see what is going on. Did he mess up the first time? Do I just pay to redo the job? Does he have any responsibility? Any guidance is greatly appreciated. If my wife sees another $1185 dollar bill she is gonna flip out.
Walter,
I didn't read all of the thread so I am not sure if anyone mentioned the fact that on occasion a weak or bad circuit breaker can cause the problem you have described. I have had it happen in the past. I replaced the breaker and all was fine.
If the breaker replacement does not work, give your electrician a call and explain the problem. If he is worth his salt, he will fix the problem at no further cost to you.

[Scot wolf]

I always thought 12 guage wire needs 20 amp circuit breakers for protection. Are you saying to use higher rated circuit breakers? That sounds like unusual advise. Care to explain?


That's what I'm saying. It is covered in article 430. You're fine with #12 on a 25 amp 2 pole breaker for a motor load.

[Rod Sheridan]

Hi, I know it's of no use, however the Canadian Electrical code allows the following overcurrent protection for motor feeders

Time delay fuse Maximum 175%

Non Time Delay Fuse Maximum 300%

Thermal/Magnetic breaker Maximum 250%

The above figures are for instances where the standard branch circuit protection would not allow the starting of the motor.

I would investigate the wiring and the strapping of the motor, perhaps the motor is dual voltage and is connected incorrectly.

Failing that, changing the circuit breaker to a higher value (such as the 25 amperes suggested previously) may solve your problem.

One thing of interest is how low the power factor and efficiency are on your motor. I have a 3HP high efficiency/power factor motor on my General 650 saw and it is only 13.7 amperes. My saw starts on a 15 ampere branch circuit reliably.

The lower performance motor on your planer may be les expensive, however there obviously is a penalty to be paid.

Please keep us posted on how you make out with your problem.........Rod.

[Rod Sheridan]

I can't type.

My saw motor is 12.7 amperes, not 13.7..........Rod.:o

[Steven Wilson]

Ron, Scott, you're both talking about implementing this circuit as a motor circuit instead of a general branch circuit (aka the 20amp breaker). Before making that change I would run the proposed solution by the local electrical inspector. I would be leery of uping the breaker while maintaining a plug in outlet box, expecially in a residence. Our local inspector wanted any motor circuits to be hardwired with a circuit disconnect box (was investigating this for my DC and compressor).

[Andy Pratt]

I should preface this by saying that I know jack about electrical work, but this seems like a thing anyone can check easily with no risk of error.

I had a similiar problem with my setup (2 machines (DC and TS) on a 30A circuit) that didn't make any sense to me and I was at a loss for why the power was cutting off. When I checked the breaker box thoroughly I realized that one breaker (my 220v breaker is two smaller switches connected by a plastic cover to operate as one switch, I believe this is normal) of the two was not fully clicking into position when I switched the two on and off (supposedly in union). It looked okay until I pressed it hard to the on position and the top one clicked in all the way, then it functioned perfectly. Probably not an issue for you if your breaker switches aren't old but thought it was worth mentioning.

[Curt Harms]

Any tradesman who expects to be in the community for any period of time is going to have to stand behind his work. Related question, are there motor rated and non-motor rated circuit breakers? The starting surge on woodworking equipment can be substantial, a circuit breaker without "time delay" would certainly have problems like you are reporting. I also had a problem with a Rikon band saw tripping a circuit breaker and it turned out to be a bad motor.

HTH

Curt

[Jerry White]

OK, Walter, any news on the cause of your problem? Electrician show up yet?

[Tom Veatch]

... Related question, are there motor rated and non-motor rated circuit breakers? The starting surge on woodworking equipment can be substantial, a circuit breaker without "time delay" would certainly have problems like you are reporting. ...

Someone please correct me if I'm wrong, but I believe all standard "residential" circuit breakers are "time delay" in that they allow some amount of overcurrent for a brief time before tripping - the higher the overcurrent, the shorter the time.

[Rob Damon]

When considering a motor load that is "close" the rating of the circuit breaker, rather than increasing from 20A to 25A, you should consider using a "high Magnetic" or HCAR type circuit breaker that is designed specifically for dealing with inherent high inrush current from a motor start, which can be as much as six times the running load of the motor. Square D and G.E. both make "HM" style plug in circuit breakers for the typical home based QO style loadcenters.

Just a suggestion.

I had an air compressor that would 7 out of 10 times trip a 20A C.B. on startup. I just changed the circuit breaker and the problem has gone away.

Rob