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Bonehead planer wiring question6/2
I have a greenhorn question about planer wiring.
We purchased a powermatic planer with spiral head that is dedicated to producing consistent thickness faceframes. The planer is single phase,15 amp, 3HP.
We start out with 23 mm thick material then widebelt sand one face to smooth. The sanded face is oriented down on the planer bed and the planer spits out 22 mm every time. The planer thickness never changes.
The problem we are having is that the planer constantly shuts down. If you run more than a few boards it seems to overheat and a thermal overload kicks in.
The planer is 15 inches wide and we seldom run material wider than 4 inches. We have excellent dust collection at the planer.
The planer is plugged into a dedicated 20 amp circuit located about 12 feet from the machine.
I downloaded the attached cut sheet this morning and I see now that they recommend a 30 amp circuit for the machine. The 20 amp breaker, however, has never tripped. As I said before, the motor is rated at 15 amps.
Can anybody opine on what the problem is? Is it possible that the motor would have an overload protection that kicks in way before any problem at the 20 amp breaker?
If you are running a 20 amp breaker you are likely running 12 gauge wire. When you bump the breaker to 30 amps make sure you increase the wire size. I believe 10 gage is called for.
I would check running amp draw for each leg of power (2). I believe you will find one leg is drawing more power which is causing the starter to trip.
From there I would check all the connections on the planer, even if you did not make them, from the plug (if there is one) through the starter and into the motor. In the motor starter there is either heaters which are designed for a specific amp draw or a dial. If it is heaters look them up and make sure they are the correct amp draw. If it is a dial make sure it is set correctly.
If you find a leg with a higher amp draw and can not find the source "hot wire" it past the planers internal wiring and check the amp draw. If it is still bad you have a bad motor.
Good luck and be safe
Thanks for the great response Bill.
Looks like this problem is over my pay grade. Will need to bring in an electrician to run these tests.
How far is the wall plug from your circuit box? If it is a long distance, you could be getting a voltage drop if the wire is too small. The motor has a running amperage of 15. It probably has a start up amperage of about 22 - 25 . That is why it recommends a 30 amp breaker. Does the machine have a factory plug or is it a plug that has been added? If it was added, check to be sure that the amp rating for it is greater than 25. It will be stamped on the plug. Check the wall socket for the same thing.
Check amp draw at machince and at service panel, any other equipment using this circuit? If amp draw is over breaker limits then larger circuit is needed. If amp draw is under then check breaker, it may be weak.
What gauge wire did you use from the motor to the outlet? Is that hot when the motor gets hot? Undersize wiring somewhere, or you have a bad motor.
Heater elements can weaken over time as well. I've had many machines start to kick out like this and they simply needed new heaters. If all else fails, mention this to your electrician.
I had a machine that would do this (3HP edge sander). The magnetic starter had a variable current limiter that was set a little to close to the nominal current draw of the machine. Bumped it up one amp by turning the dial and the problem went away permanently.
Leo is correct. Pull the cover off of your start/stop case and look for the current overload device and with a small screw driver dial it up a little higher, I too believe your problem will go away.
If the breaker and the cord going to the machine isn't warm then you don't have to increase the amperage going to the machine.
I'm with Leo. I recently bought a 3hp shaper and it would kick off after a few short minutes and then after a few minutes would start back up until the next time. I dialed the switch a notch and it has never kicked off.
We ran a few boards through the planer today but not enough to make it shut down.
As soon as we can sort of isolate the wire temperature we will then move to adjusting the adjuster gizmo. I am optimistic it will work. Will report back.
I agree with Leo. My old 5 hp Unisaw required me to turn the dial in the starter. The guys at the service shop told me to do it. Those are high quality Marathon motors. I wired the building and its correct. It never tripped the breaker.
In retrospect, I think the problem may lie in all of the starter switches. The motors may be good. His Powermatic is made in Taiwan(the modern Heirloom quality). The Leeson's & Marathons are US made. However, the starters might be junk. At the very least they may be incorrectly calibrated.
There is another possible problem. I had a Jet band saw that had one of the 230v motors. It cooked the motor. They sent me another and it cooked that one. They did not like the industrial park power. The sparky came and measured it about 215v. When they have 3 phase power lines the single phase power is not 220v. I bought a good Marathon motor rated 208v - 230v. It was fine forever. Same starter.
Your Powermatic is one of those 230v motors. What is your power source?
I will say this about Powermatic. About two ears ago I ordered one of their big feeders for a shaper and the motor took forever to wind up and get any speed. Called them and told them that I thought the capacitor was bad and described what it was doing and they agreed. They sent me a new capacitor and I put it on and it didn't help. Calls them back and they sent me a new feeder and told me to keep the other for parts. Pretty good I thought.
I got a good deal on a Rockwell bandsaw that would shut down after a few minutes of use.