Question for electrician guys.

[Fritz Maurer]

Want to run 25 hp electric motor with 50 extension cord, as both generator and shredder are portable and must be moved around.

My concern is the motor says 60 amps @ 230 volts . I would like to retain the twist- locks on the generator , which are currently Hubbell 600v / 30 amp.

The motor was off an air compressor wired with 10 ga. solid wire @ 460 v.

Do i have to toss the twist-locks and go to a heavier plug, like a dryer plug or something , I really don't know what to look for.

The application is not going to require full horsepower, nor have a high starting load, and run unloaded 50% of the time.

 

[TheBartman47]

I use Hubbel 50A twist-lock style connectors with 6 gauge wire to run my large stuff.

https://www.hubbell.com/hubbell/en/products/electrical-electronic/wiring-devices/locking-devices/50a-twist-lock/c/2027737

You say the motor is labeled 60 A @ 230 V but then say it was wired @ 460 v. Something is not right here.

 

[Janicholson]

At no more than 50 ft, 8 gauge at 460 volts or 6 gauge at 240. 4 wires L1,L2, neutral, Equipment ground. (the last sentence might not need the Neutral if the load has no mid level 120 or 240 single phase, from L1 or L2 to neutral. Remember, the 460 volt source/load operates at about 1/2 the amps that 240 does. Jim

 

[Fritz Maurer]

I use Hubbel 50A twist-lock style connectors with 6 gauge wire to run my large stuff.

https://www.hubbell.com/hubbell/en/products/electrical-electronic/wiring-devices/locking-devices/50a-twist-lock/c/2027737

You say the motor is labeled 60 A @ 230 V but then say it was wired @ 460 v. Something is not right here.

I neglected to mention that's how it was wired on the compressor.... it is now 230.

 

[used red MN]

What kind of material do you shred?

 

[Mule Meat]

What kind of material do you shred?

+ Is that 60 Amps start or 60 Amps continuous? Start up amps are normally much higher than continuous run as you should already know. Should have a tag with that information on the motor.

 

[buickanddeere]

Generator has to be 240V instead of 480V ?

 

[Fritz Maurer]

What kind of material do you shred?

Topsoil / leaf mulch

 

[John T]

Even if you arent using it at full load, ifffffffffffffff the motor running at 230 volts ???? ever were to draw 60 amps ?????? ( I cant say from here what alls being powered ) Id still use wire with 60 amp capacity IE 4 Gauge even if 6 suffices to reduce line voltage drop but thats just me I prefer over engineering lol

Are you gonna use 230 or 460 ???????? if 460 things change

John T

 

[Fritz Maurer]

+ Is that 60 Amps start or 60 Amps continuous? Start up amps are normally much higher than continuous run as you should already know. Should have a tag with that information on the motor.

Well, I'm not too sure... I was guessing that 60 amps was at max load....but will never need all 25 hp...got a V-4 Wisconsin on there right now, and it pretty much just loafs along ...not even at max governed speed. That's why electrifying seems attractive... the motor is 1750 rpm, freshly reconditioned, and i have only change the taper lock bore to make it fit my machine.

The other side of this coin is trying to find an engine with a no. 3 bell housing.... haven't had much luck so far.... for electric I already have all the serious components except for an extension cord.

 

[Geo-TH,In]

+ Is that 60 Amps start or 60 Amps continuous? Start up amps are normally much higher than continuous run as you should already know. Should have a tag with that information on the motor.

Agree lock rotor amps will be many times higher. Look on the name plate for LRA and is the 460 v single or 3 phase??

I'm confused, the pic below is a 3 phase AC generator. I'm guessing a 25 HP motor has to be 3 phase.

 

[Fritz Maurer]

Generator has to be 240V instead of 480V ?

According to the tag, it can be high voltage. But that would mean changing the meters and possibly voltage regulator.... there just isn't any information out there on Delco generators ... having a shop do it would probably cost $1000... 50 ft of 4- 6 is about $250.

 

[miangus]

Something doesn't sound right, UGLY's recommends a 50-amp breaker for a single phase 10 HP motor and a 50-amp breaker for a 25 HP three phase motor at 460-volts. A 25 HP motor at 240-volt three phase needs a 100-amp breaker.

 

[John T]

PS Earlier you mentioned 60 amps for the 25 HP Motor and Ifffffffff full load were actually 60 amps I suggested 4 gauge wire simply to reduce line voltage drop however I cant know all the details but

FWIW based on which charts I looked at the FLA for a three phase 25 HP Induction Motor at 230 was 60 to 68 and at 460 30 to 34 Amps....

SO IFFFFFFFFFFF you run at 460 in that case then 50 amp or 6 gauge wire would suffice for an extension cord on a 25 HP Motor. In that case 50 amp rated plugs and receptacles can suffice. A NEMS 14-50 (plug or receptacle) is rated for 50 amps

Sizing wiring and receptacles is easy off a chart as long as you know the actual current and voltage but I dont know all that for sure so dont take my advice.

CIRCUIT BREAKERS You may want to consider use of an HACR Breaker for your application once you decide the current and voltage etc

John T

 

[used red MN]

but will never need all 25 hp...got a V-4 Wisconsin on there right now, and it pretty much just loafs along

I think that if that V4 is powering it now a 10 - 12 hp electric would do the job. Of course I’m not sure how much you need to increase the pulley speed.

 

[Fritz Maurer]

I think that if that V4 is powering it now a 10 - 12 hp electric would do the job. Of course I’m not sure how much you need to increase the pulley speed.

Could be.... i was never clear on how electric/gasoline hp compared.

 

[RJKeith]

+ Is that 60 Amps start or 60 Amps continuous? Start up amps are normally much higher than continuous run as you should already know. Should have a tag with that information on the motor.

At 25 HP at 220 Volts three phase it will be 60 amps to run, starting amps will be over 300 amps. So:

First, how big is your generator. My general rule for sizing is 1KW per HP, then twice to start with a reduced voltage starter, three times for across the line starting. So if you are starting the motor across the line, you will need about a 75KW generator to run the motor.

Second, by code your motor circuit needs to be sized at 125% the Full Load Amps, or running amps. That means at least 75 amps for your situation. The 30 amp plug is a nogo.

Also, we are assuming a three phase motor. Is that 30 amp plug for a three phase or single phase circuit. A 30A 120/240 volt twistlock is a common plug on a single phase generator. Something isn't adding up.

 

[paul]

I’m struggling to follow this thread, often electrical threads are fun here.

This one I’m not sure what is trying to be accomplished? Seemed a lot of cross over from different voltage specs to different plug types not really sure where we are headed.

25 hp electric motors are the real stuff, anything over 10 hp needs some pretty stout wiring. And the inrush, or starting loads get to be an issue that smart folk end up dealing with, not folk like me that read a few wiring pamphlets.

Paul

 

[Tramway Guy]

Starting current will be whatever the generator can deliver.. As long as you start it unloaded, it will come up to speed.

I would rewire to 460 volts. The regulator shouldn’t need changing; the Delco nameplate already says it can do 460 volts.

 

[Mule Meat]

I’m struggling to follow this thread, often electrical threads are fun here.

This one I’m not sure what is trying to be accomplished? Seemed a lot of cross over from different voltage specs to different plug types not really sure where we are headed.

25 hp electric motors are the real stuff, anything over 10 hp needs some pretty stout wiring. And the inrush, or starting loads get to be an issue that smart folk end up dealing with, not folk like me that read a few wiring pamphlets.

Paul

That's me..
If you look at the tag.
240 volts - 90 Amps. Starting or running amps.

It's going to take one heck of a huge generator to produce 90 amps at 240 volts. It would need to be in the 20+Kw range.

Coming off of the power grid. I would install a sub panel and wire it for 240 volt three phase.