Connection Inside Motor Terminal Box

[Lemming]

This thread astounds me.... I have never come across a motor of any size without a terminal block....

 

[krakenfan69]

+1 for the multi taps TConnelly mentioned. If I have to use split bolts I always "backtape" them with a few layers of electrical tape so they don't get the connectors all gummed up after months/years of use. Then Rubber tape then more electrical tape. If you have ever had to go back to one to rework it you will appreciate being able to slice the tape off and having nice clean split bolts to work with. I still prefer the multi taps however.

Kraken Fan #69

 

[MasterBlaster]

I see nothing wrong with wire nuts if the conductors are small, like up to AWG.8. And always be sure to tape the connections well after nutting. Larger connections I would use a split bolt, followed by a layer of vinyl tape, a layer of rubber splice tape then another layer of vinyl. If done properly you will never have an issue.

It is a code violation to tape wirenuts. The NEC takes the position that if a wire-nutted connection "needs" tape, either the nut is installed improperly or a nut is inappropriate for the splice.

Split bolts are tough to beat. The first layer of tape should be applied sticky side OUT. That way, when the tape must be removed, a simple slice with a knife allows the tape to be easily pulled away from the connector.

 

[rpoet]

I've used these with smaller motors (>10hp) with good results.

http://www.mcmaster.com/#6878k97/=qi9z1d

No vibration concerns, and easy to remove/reuse. I also use these for field wiring in there's no room for traditional terminal blocks in the enclosure, and I have more than two wires that must be joined together. Much more secure than "regular" wire nuts.


-rpoet

 

[dogleg43]

This thread astounds me.... I have never come across a motor of any size without a terminal block....

My experience has been just the opposite. Only on the smallest fractional HP motors have I ever seen a TB inside the peckerhead.

As far as how to make the connections, this may turn into an "old school" vs "young buck" type of thing. The tried and true method is ring tongue terminals bolted together. Then taped with any of many variations of tape. Very dependable but time consuming. The Polaris style connectors seem like the new "best" way tome.

 

[Jeff23spl]

My experience has been just the opposite. Only on the smallest fractional HP motors have I ever seen a TB inside the peckerhead.

As far as how to make the connections, this may turn into an "old school" vs "young buck" type of thing. The tried and true method is ring tongue terminals bolted together. Then taped with any of many variations of tape. Very dependable but time consuming. The Polaris style connectors seem like the new "best" way tome.

You are in USA and Lemming is from oversea, this probably give a point to my theory.

 

[Jeff23spl]

It is a code violation to tape wirenuts. The NEC takes the position that if a wire-nutted connection "needs" tape, either the nut is installed improperly or a nut is inappropriate for the splice.

Split bolts are tough to beat. The first layer of tape should be applied sticky side OUT. That way, when the tape must be removed, a simple slice with a knife allows the tape to be easily pulled away from the connector.

The proper tape isn't to provide isolation, but as an add-on to keep the wire-nut there in case of loose connections in house installation. If the tape is used for something else, it's improper installation.

 

[JesperMP]

This thread astounds me.... I have never come across a motor of any size without a terminal block....

I think it is a US thing.
Have seen it on equipment from the US only. Have also seen US electricians do the wire-nut thing.

I see nothing wrong with wire nuts if the conductors are small, like up to AWG.8. And always be sure to tape the connections well after nutting.

The tried and true method is ring tongue terminals bolted together. Then taped with any of many variations of tape.

 

[allscott]

It is a code violation to tape wirenuts. The NEC takes the position that if a wire-nutted connection "needs" tape, either the nut is installed improperly or a nut is inappropriate for the splice.

Split bolts are tough to beat. The first layer of tape should be applied sticky side OUT. That way, when the tape must be removed, a simple slice with a knife allows the tape to be easily pulled away from the connector.

This. I have an irrational hatred for tape on wire nuts. If a wire nut comes loose it is generally because of one of 3 different reasons.

- Not enough insulation stripped off the wires.
- Wrong size of wire nut for the size or number of wires used.
- Wrong application (vibration)

I will admit I will use them for small motors where vibration isn't an issue but other than that I use ring terminals and a screw for smaller wires and split bolts for big ones.

I was taught and still use cambric, spicing tape and 33 for insulating but have taken a liking to the rubber boots as well.

 

[MasterBlaster]

The proper tape isn't to provide isolation, but as an add-on to keep the wire-nut there in case of loose connections in house installation. If the tape is used for something else, it's improper installation.

Regardless the reason for tape, a taped wire nut is a code violation.

 

[AllanJacobs]

We have tried Polaris connectors with no luck, they would strip out or vibrate loss or because they were aluminum they would work loose. We have had very good success with split bolts, glass tape would sticky side out , rubber tape then vinyl tape. takes a while to connect but does not fail.

 

[dogleg43]

We have tried Polaris connectors with no luck, they would strip out or vibrate loss or because they were aluminum they would work loose. We have had very good success with split bolts, glass tape would sticky side out , rubber tape then vinyl tape. takes a while to connect but does not fail.

Good info to know, Allan. The subject of this thread has been beat to death on other electrical forums, especially what tape to use on what layer.

It seems like the best approach is to use what works in your enviroment and if going to a different site or customer then ask them how they normally make up motors and go from there.

Just as an example, my company almost got ran off of a job because we pulled in a spare brown wire to use as future pull wire. The plant electrician went bananas!!. Methods of motor lead termination is a similar deal.

 

[Temper]

I work in a sawmill in Canada. All of our 5HP up to 20 HP motors use marettes and tape. Very few of our motors come with bolt terminals except for very small fractional horsepower motors. For bigger motors, we use split bolts and tape. I'm going to have a look in the Canadian Electrical Code tonight.

 

[iant]

This thread astounds me.... I have never come across a motor of any size without a terminal block....

I have seen many mate