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05-31-2023, 12:17 PM
(This post was last modified: 05-31-2023, 01:29 PM by davco.)
I talked to a Baldor Electric Motor Service shop, and they told me my motor isn't starting because I ran 10 gauge wire, instead of 8 gauge to the
220V Single Phase 5 HP Baldor Motor. It's on a 30amp breaker.
Just curious what experience you guys have had and what your wiring setup is before I go out and spend $100 on 8 gauge wire, also what amp breaker are you using?
From most of the posts I read, I had thought most guys were using 10 gauge.
My motor is rated at 21.8 amps.
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Unless it is a long wire run, it should start. Maybe not ideal, but I can't locate the formula provided in the NEC right now. It uses a specified current draw instead of the motor label.
But, I can tell you that I have a 5hp Baldor 3ph running on 12ga and a 15a breaker. been that way for 15 years or so.
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What's the motor doing when you try and start it? My guess is it probably doesn't have anything to do with the gauge wire used.
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I'm thinking at 220 volts you might draw 20 amps under normal load but starting under load will need more. 30 amps on 10 ga. is normal wiring (except for possibly a really long run. The FLA (full load amps0 on that motor is probably around 24amps. If the motor won't start and run with the load removed, then there's something wrong with the motor or wiring; and it's defiantly not 10ga vs, 8ga! The shop just didn't want to spend any time helping you figure out the problem.
Not to fret though. You've asked people willing to help sort it out right here. We're going to need a little more information though. Obviously the first thing to check is if there is power to the correct terminals as shown on the data plate. If there is, then let's dive in. Is it a brand new motor? What happens when you power up the motor? Nothing? Does the breaker trip? Did the motor ever feel warm? And, if so, can you detect any hint (smell) of burnt wiring? (hopefully not!) Which leads to the next question, is the thermal overload tripped? (in the normal position, the red button doesn't stick up very far. If it's up more than about 1/4", it could be tripped and some require a pretty hard push to re-set.)
Once you've answered these questions, we can help more. Most of these I've worked on have a centrifugal switch that turns off the start caps. Some have another thermal type switch that switches power to the run caps. Then of course there's the caps themselves, and how they're wired. Two came into my shop that some uninformed individual had pumped the end bells completely full of grease; I saved one. So if you're not sure how to do something ask before you let the magic smoke out; There's no way to get it back in.
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06-01-2023, 06:08 AM
(This post was last modified: 06-01-2023, 06:18 AM by davco.)
New motor
I measured voltage in the junction box on the motor body and both incoming wires have 120v.
When powered up the motor does nothing, no smell, no sounds.
I brought the capacitors into that service shop and they said both were good
Can't see any overload/reset button on the motor
What else to test next?
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Some progress
An electrician stopped by and determined that I did not have the double pole breaker in the correct AB slot.
So now it starts, but the breaker flips after 5 seconds consistently.
I reached in and turned the impeller by hand, half of the rotation it glides, the other 180 it feels like it's binding. Is that normal?
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06-01-2023, 07:53 PM
(This post was last modified: 06-01-2023, 07:57 PM by Allen.)
(06-01-2023, 02:25 PM)davco Wrote: Some progress
An electrician stopped by and determined that I did not have the double pole breaker in the correct AB slot.
So now it starts, but the breaker flips after 5 seconds consistently.
I reached in and turned the impeller by hand, half of the rotation it glides, the other 180 it feels like it's binding. Is that normal?
The motor should turn freely by hand. With the belts off the motor should turn full rotation freely and cost to a smooth stop.
Al
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My CV has the Leeson motor, and it's been running on 10 gauge wire and 30 amps for maybe 6 years with no problems. My previous Oneida was refitted with the exact same motor and it ran for probably 7 years like that before i sold it. I think you got a defective motor, and I suspect that CV will provide a new one. Of course the problem is you have to disassemble the thing to change them, and that's actually a royal PITA.
I started with absolutely nothing. Now, thanks to years of hard work, careful planning, and perseverance, I find I still have most of it left.
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(06-02-2023, 06:18 AM)fredhargis Wrote: My CV has the Leeson motor, and it's been running on 10 gauge wire and 30 amps for maybe 6 years with no problems. My previous Oneida was refitted with the exact same motor and it ran for probably 7 years like that before i sold it. I think you got a defective motor, and I suspect that CV will provide a new one. Of course the problem is you have to disassemble the thing to change them, and that's actually a royal PITA.
Thanks Fred
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The impeller should spin freely and should also be balanced. If you feel a drag, no matter how slight, either it, or the motor has issues. If the unit did run it would probably shake itself apart. Do you think the binding is enough to stop the motor from coming up to speed? That could be drawing more than 30a, and depending on how many times it's been tripped, the breaker may now be tripping at a (measurable) lower current.
At this point the I think the easiest thing to check is if the impeller is just too far forward or back causing the "binding". I don't know how much of a project it is to remove the impeller, but that would my next step so I could test the motor with no load. If this is a brand new unit, before I started tearing it apart, I would be speaking with your retailer then the manufacturer. You might want to forget to mention the two 120v lines. (they're actually just two wires connected to the same lug, so there's no current flow; same as a 120v motor connected to neutral without a hot or vise versa.)
I just remembered you had the caps tested. If they're wired wrong or swapped, it could also be tripping the breaker. That won't cause or fix the "binding" though.
Sign at N.E. Vocational School Cabinetmaking Shop 1976, "Free knowledge given daily... Bring your own container"
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