my mistake, the 1hp motor pictured https://www.machinerypartsdepot.com/product/SP23PH
requires boring the pulley to 7/8" from 3/4"
that's for a 1J head, the motor won't work on a 2J , i didn't realize you had a 2J
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Bridgeport Motor Issue (Video)
- Thread starter Ceej0103
- Start date
requires boring the pulley to 7/8" from 3/4"
that's for a 1J head, the motor won't work on a 2J , i didn't realize you had a 2J
Hey guys, got an update for you.
So the motor surge tested fine. As mentioned previous, looks like it's been re-wound as it no longer has 9-wires and only 3. The place that tested the motor confirmed that it was hardwired for 480v. I've been running at 240v. Looks like there's mixed schools on whether underpowering a motor will hurt it, but the surge testing confirmed the motor is still in perfectly good condition and the servicer said he had it running just fine. He did say I was looking at $700-750 to rewind it for 240v. That's not worth it....I can get a new one for close to that.
Before I go that route, I'm going to see if I can find a step-up transformer option to get me to 480v. Does anyone know if there's a VFD out there that provides single to three phase output + a step up from 240v to 480v? Any advice on the most efficient way to do this would be great. If it's cost prohibitive, I may just order a new motor.
Remains a mystery as to why it would work for several months and all of a sudden it wont.
So the motor surge tested fine. As mentioned previous, looks like it's been re-wound as it no longer has 9-wires and only 3. The place that tested the motor confirmed that it was hardwired for 480v. I've been running at 240v. Looks like there's mixed schools on whether underpowering a motor will hurt it, but the surge testing confirmed the motor is still in perfectly good condition and the servicer said he had it running just fine. He did say I was looking at $700-750 to rewind it for 240v. That's not worth it....I can get a new one for close to that.
Before I go that route, I'm going to see if I can find a step-up transformer option to get me to 480v. Does anyone know if there's a VFD out there that provides single to three phase output + a step up from 240v to 480v? Any advice on the most efficient way to do this would be great. If it's cost prohibitive, I may just order a new motor.
Remains a mystery as to why it would work for several months and all of a sudden it wont.
VFDs need the feedback from the motor to work. Trying to run them into a transformer will likely cause them to shut down in confusion. You might be able to do it the other way and use a transformer to go from single phase 240->480, then a 480V VFD.
You can use transformers on rotary phase converters though those aren't cheap either. You could build one for a more reasonable price.
I'm also confused why it would work for a while then stop. I'm glad that the shop was at least able to explain what's up though.
If it were me, I'd replace the motor with a dual voltage or 240V and use the 240V VFD.
I don't know if it works that way, but maybe build a RPC that outputs 480V and lose the VFD entirely. I'm not that familiar with RPCs.
You can use transformers on rotary phase converters though those aren't cheap either. You could build one for a more reasonable price.
I'm also confused why it would work for a while then stop. I'm glad that the shop was at least able to explain what's up though.
If it were me, I'd replace the motor with a dual voltage or 240V and use the 240V VFD.
I don't know if it works that way, but maybe build a RPC that outputs 480V and lose the VFD entirely. I'm not that familiar with RPCs.
Low to high volt VFD are available, but they're spendy. You might as well have it rewound. My experience with high volt motors run on lower voltage is that they run, but obviously nowhere near their rated output and that starting can be hit and miss. You might be able to rewire that motor (not rewind) if you can find and access where wires from each winding are joined. Ironically, I could have pointed you in the right direction for wiring the 9 wire up for low volt.
That's a great idea. I'm picking the motor back up on Monday and I'll tear it down and see what I can see. If you go back to like Page 3 of this thread you'll see pictures of the top of the motor and where the 3 wires are originating. They wrap around the top of the windings in a yellowish sleeve. Although it's been hardwired for 480v, will I still definitely have 9 individual leads in there somewhere that have been joined? If I can find them, I'll have to test to figure out which are 1-9. I think I saw some youtube videos on how to go about determining that.
= no kidding!!
"Hardwired for 480" I didn't know that was a thing? Don't they usually have two wiring options, 220 and 440?
Final update for this one. There's still a chance I can un-do the hardwiring at 480v in the 1 1/2hp motor, but I just decided to upgrade to a 2HP motor instead. I'll dig in to the 1 1/2 hp motor to have as a backup or sell it on ebay. I'm sure someone out there is running 480 in their shop and could use it.
Ended up going through matacoinc.com for the purchase. Dennis over there (i think that was his name) gave me a decent price on the 2HP and the new vari-discs. I bench tested the motor using the VFD that was hooked up to the 1 1/2hp motor and it was golden. Even at only 5hz, I couldnt overcome the shaft from spinning. At a full 60hz its nice and quiet and gives me a lot more output than the 1 1/2hp motor did. I guess that's to be expected when you run a motor at 240v when it's wired for 480v. If memory serves me correct, thats a recipe to get about 1/4 of the capability out of the motor. So the VFD checks out fine. Still no rhyme or reason as to why the VFD ran the 1 1/2hp for 9 months and then failed to run it.
The machine really comes alive in high gear and running up to 3k RPM+. I can really tell that I wasn't getting a full 1750rpm out of the 1 1/2hp motor because with the new 2HP wired for 240v, it feels like the machine is about to blast off and enter orbit.
Thanks everyone who donated your time to troubleshooting this issue. Much appreciated.
Ended up going through matacoinc.com for the purchase. Dennis over there (i think that was his name) gave me a decent price on the 2HP and the new vari-discs. I bench tested the motor using the VFD that was hooked up to the 1 1/2hp motor and it was golden. Even at only 5hz, I couldnt overcome the shaft from spinning. At a full 60hz its nice and quiet and gives me a lot more output than the 1 1/2hp motor did. I guess that's to be expected when you run a motor at 240v when it's wired for 480v. If memory serves me correct, thats a recipe to get about 1/4 of the capability out of the motor. So the VFD checks out fine. Still no rhyme or reason as to why the VFD ran the 1 1/2hp for 9 months and then failed to run it.
The machine really comes alive in high gear and running up to 3k RPM+. I can really tell that I wasn't getting a full 1750rpm out of the 1 1/2hp motor because with the new 2HP wired for 240v, it feels like the machine is about to blast off and enter orbit.
Thanks everyone who donated your time to troubleshooting this issue. Much appreciated.