Woodworking Talk banner

Electrical question help

2K views 13 replies 9 participants last post by  GeorgeC 
#1 ·
What is the name of the little clamp I can use on 1/0 cable to attach another cable to it. I have 1/0 cable coming into my shop on one end of the building. Where the cable enters the shop , it goes into a 12 x 12 junction box. It leaves the box and goes in one direction in the wall going on one side of the shop to my breaker panel. I want to tap into that cable in that box with another 1/0 cable to hook up my generator.

What is the name of the clamp that allows me fasten the cables together. My old electrician buddy says they used to call them gurneys.

Basically I want to strip some insulation off the 1/0 able and attach another 1/0 cable to it. But I need to know the name of the clamp to order some. My retired electrician is guiding me but with the virus he isn't coming around and he can't think of the name of them either.
 
#3 · (Edited)
Thanks Lenny. That is exactually what I was thinking of but couldn't think of the name to search it. Thanks.

One last thing, I know they have this gray looking stuff in a tube you have to put on alum cable to prevent oxidation or?? But my main power cable (1/0) is alum. I will be connecting copper to it. Do you know if I have to have a special clamp and/or use that gray stuff in a tube. My elect talks about electrolysis of 2 different types of metals.

Whats your thoughts?
 
#7 ·
DO NOT use those split nuts to attach a copper wire to an aluminum wire, you run the risk of a "hot" connection that could start a fire. It's not safe, in most places in the world it's not legal and I've also heard that your insurance will be void if they find that in the smoldering ruins of your shop/house.

There are lots of different ways to attach aluminum to copper safely, one is this:

https://www.galco.com/buy/King-Innovation/95135

If in doubt, hire an electrician, that way it's safe
 
#8 · (Edited)
Yes to hiring an electrician if n doubt.

But... split bolt connectors are authorized for AL/CU

c https://commerce.ilsco.com/e2wShopp...k=2100001183:3100012168:3100012495:3100012902

NoOx is the generic name for the paste you asked about.

As far as hooking to a generator, previous posters are 100 % right.

You must have some type of positive lockout mechanism.

If not, you could backfeed the power line with your generator and direct connection. A lineman working on the line to restore your electricity could be shocked.
As the transformers work, they step down a high voltage to 220 to come into your house.
If you feed the transformer backwards, that voltage gets stepped up. With lower amperage. (Remember Ohm’s law). Voltage = Amps X Resistance.

However.
Only .01 amp (10 miiliamps) is enough to cause cardiac arrest.

So an interlock is mandatory so only one or the other is ever connected.
It is illegal everywhere to backfeed or have the ability to backfeed a public transmission line.

Sent from my iPhone using Tapatalk
 
#9 ·
Cool Link Lenny, thanks!

I had no idea they made split bolt connectors for aluminum to copper. You learn something new every day!

Tewitt - make sure you get the ones Lenny linked to, they are made of aluminum alloy and have an extra spacer bar so the aluminum wire never touches the copper one.
 
#11 ·
Your electrician buddy was close to having it right- the old timer term for a split bolt was a "Burndy", not gurney.
Burndy was an original producer of the split bolt connector, and was the only brand available in most places, so they were simply referred to in the trades as Burndy's.

https://www.hubbell.com/burndy/en/P...and-Terminals/Split-Bolt-Connectors/c/2147254

Kind of like channel locks and vice grips.
And yes, you can get correct connectors for AL to CU. You can also minimize oxidation with a product like Penetrox brand anti oxidant (also made by Burndy).

A quick tip: once you have tightened the split bolt, hold the nut part in free air with channel locks and smack the top of the bolt with a hammer a few times. You will get at least another half turn on the nut afterward.

If you make oxygen free splices, you probably can forego the Penetrox. You should have on hand at least a couple types of splicing tape to make a correct connection. Split bolts have many sharp edges that will cut right through regular scotch 33 or 88 vinyl. A healthy ball made with Scotch 23 rubber splicing tape or 130C linerless splicing tape, followed by several tightly wound half laps of 33 or 88 will minimize the chance for premature failure. Be sure to fill all the voids in the connector. And if the splice points are subject to vibration, a couple wraps of friction tape will further lessen failures.

The fact is that making low resistance, low oxidation rate, highly reliable connections in feeder size cables is usually better left to a professional.

I will not speak to your reasons for splicing as I do not know the entire scope of your project. I would, however, hope that you would carefully think about your project and take safety seriously if you plan to back feed your home electrical system. I might be the guy on the other end of the pole repairing your incoming line after the storm.
 
#12 ·
There are bi-metal connectors that allow copper to aluminum. I am a lineman and we make copper (by the beach) to aluminum connections all the time. The aluminum will generally be above the copper on the connection.

There are also insulated connectors you can choose that we use in the underground for secondary voltage and service connections. They are quick, easy, water resistant, and bi-metal. One of the manufacturers we use is Utilco.

As far as back feed and generators go, lineman protect themselves from backed in EVERY situation while we are working on the primary or secondary side of a transformer or wire off of a transformer during an outage. We don't rely on the customer or a customers breaker or transfer switch to protect us during generation.
 
#13 ·
Despite the above advice in most districts you need a permit to install a transfer switch and generator, your questions should be answered by the licensed electrician doing the install, not members of a woodworking forum.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top