Potheads - electric, not narcotic

[Trojan]

Does anybody have these devices on their system? Pothead cable termination and means of disconnect. 4,000V - three phase. 3 conductor PILC cable terminates in a compund filled cast iron body. Hand operated porcelain covered plugs connect to overhead wires thru rubber covered tap wires. G&W Specialty Electric made them up until about 50 years ago. We stopped operating them while energized about 5 years ago.

[Pootnaigle]

Ummmmmmm Cant say I have seen one like that But I have made a few with that Blue Goop innem.the bodies were however made with porcelain.

[rob8210]

PILC 3 phase potheads were very common around Ontario for years, mostly on 4kv distribution but they are getting to be very old and most places have started programs to replace their PILC cable. I have never run across that particular setup , usually we have a set of solid blade switches above the pothead going onto the main line. In the old days they would be enclosed cutouts. Positech cutouts were used on single phase transformers and some 3 phase transformers but could only be operated by hand, even seen a few on 13.8kv.

[T-Man]

We had those in our 4KV manhole system. There were spacers shaped just like the glass in your picture They had a female side on bottom and a male end on top so you could install the spacer beween the cap and the Pothead. We also had spacers that were made for grounding they had a slot on the side of the spacer with a reciever for a ground stud to slide in. The grounds were called cluster grounds because they had one ground clamp and three spliced leads branching off so you could ground a three phase pothead. Two guys would open those leads one at a time and hold your rubber glove on the cable end to cover it while your partner would install the spacer then you would place the lead into the top of the spacer. Close work and dark enough in a manhole to see the arc when you seperated the lead and dropped cable not load. If ya dropped load the arc was yellow and barking pretty good.

We had oil filed potheads on our overhead like that but the leads were hardwired and there were switches above for disconnects. The switches were the old porcelin boxes and in order to isolate and ground that pothead you had to open the fuse or switch doors and unscrew the leads and remove them, then coil them in the clear. The porcelin boxes were not rated for ground stress so everything had to be climbed de-energized then tested dead and climbed again to open the leads, then climbed again to install grounds. Lots of work involved and no bucket trucks most of the time.
The riser cable in these were paper lead cable, Three conductors wraped in oiled paper covered in lead, heavy stuff.

[Trojan]

the old ones were filled with black goop. The new potheads (not operable) are filled with blue goop - which has to be the stickiest substance ever invented.
We have a spacer that you plug in to the pothead side then you plug the tap into the spacer top. There is a porcelain between them. It has test points so you can test phasing and circuit displacement.
Our grounds are cluster grounds also. We used to plug them into the pothead by hand. Then OSHA came along and said you have to connect grounds with a hot stick. The company didn't like that common sense rule but they ended up buying brass adapters and that's how we do it now.