DocDisaster
New User
- Location
- United States
- Occupation
- Electrician
What is the most efficient way to terminate a 450HP, 460VAC, 12 lead motor? Are there any multi-tap connectors available with a sufficient amp rating?
450 HP motor termination
- Thread starter DocDisaster
- Start date
- Status
- Location
- Illinois
- Occupation
- retired electrician
The only thing I ever use for motor terminations is compression lugs with bolts and nuts. The joints would either be taped with rubber and vinyl, or if possible, insulated using Raychem GelCaps.
Before anyone comments, the rubber is installed sticky side out as required by the instructions for at least one brand of rubber tape, to make the removal easy and avoid the necessity of using varnished cambric as the first layer of tape.
Before anyone comments, the rubber is installed sticky side out as required by the instructions for at least one brand of rubber tape, to make the removal easy and avoid the necessity of using varnished cambric as the first layer of tape.
- Location
- San Francisco Bay Area, CA, USA
- Occupation
- Electrical Engineer
Yeah, I agree, but I’m kind of old school about motor connections, I’ve seen too many failed ones in the field.
Besides, the largest “Polaris” type connectors I’ve seen are 4 x 3/0 and even if you use parallel conductors, that isn’t going to get you there for a 450HP motor.
petersonra
Senior Member
- Location
- Northern illinois
- Occupation
- Semi-retired engineer
they go up to 750 mcm. Not sure they are UL listed at that rating though
- Location
- San Francisco Bay Area, CA, USA
- Occupation
- Electrical Engineer
True, but motor leads are usually extra flex conductors with a high strand count, like Class K or better, and you have to use the Polaris Grey connectors, which stop at 3/0 for the line side (2/0 for the motor lead side).
In fact come to think of it, most of the large motors I’ve made up in the last 20 years or so, especially 12 lead, either come with lugs already crimped to the motor leads, or a stud / terminal block in the peckerhead. In either case, that would make it far simpler to just use the old school method.
In fact come to think of it, most of the large motors I’ve made up in the last 20 years or so, especially 12 lead, either come with lugs already crimped to the motor leads, or a stud / terminal block in the peckerhead. In either case, that would make it far simpler to just use the old school method.
- Location
- Bremerton, Washington
- Occupation
- Master Electrician
I agree with Don, compression lugs , SS hardware, but I use T&B motor stub boots. Split bolts are obsolete.
- Location
- Bremerton, Washington
- Occupation
- Master Electrician
I had a 75 hp motor connected with black Polaris connectors and they failed. Replaced with gray. And on the compression lugs I had a kit from Burndy with lugs for fine stranded wire
- Location
- San Francisco Bay Area, CA, USA
- Occupation
- Electrical Engineer
Those were new to me, had to look it up. I like them!
- Location
- Bremerton, Washington
- Occupation
- Master Electrician
I used these on water pump motors and sun pump leads. Carried all sizes in storeroom .
I had to reconnect a 100 hp 460 v fire pump motor that had been connected with split bolts and insulation putty. The putty got into the wire stranding and was many hours to clean it out
Only disadvantage is motor stub boots make it easier for mechanics to change motor. Dons gelcaps would stop that
I had to reconnect a 100 hp 460 v fire pump motor that had been connected with split bolts and insulation putty. The putty got into the wire stranding and was many hours to clean it out
Only disadvantage is motor stub boots make it easier for mechanics to change motor. Dons gelcaps would stop that
- Location
- Illinois
- Occupation
- retired electrician
The GelCaps are easily removable and reusable . I like that they are completely sealed against moisture. The are not cheap, but when you look at the labor costs in high labor rate areas like mine, they are very competitive with taping.
- Status