Electric power transmission lines question
- Thread starter walterjay
- Start date
transmission line engineer here. hard to tell from picture because of angle and glare, but it appears to be terminators with a transformer to step the voltage down with jacketed underground conductor. likely a feed for a nearby building. the white caps are probably animal protection. now that I've looked closer the devices mounted directly to the cross arm at the top could be meters, and the transformer could be stepping the voltage down to power the computer that is monitoring the signal from the meters. it weird to see that on the line because typically the metering is done at the substation.
Looks like they could be capacitors for power factor correction?
Looks like SUB-transmission line monitoring equipment.
Just a guess.
Just a guess.
JTK
$100 Site Donor 2025
I see open switches, transformers and insulators.
The square boxes are capacitors for power factor correction.
Looks like they still have some work to do. All the switches or cut outs as my lineman buddies call them are hanging open. There should be a wire running from the top of the cut outs to lines on the very top. Those cut outs have a load break on them them so when you open them under load they don't arc. That's what the flag shaped thing is on them.
Looks like they still have some work to do. All the switches or cut outs as my lineman buddies call them are hanging open. There should be a wire running from the top of the cut outs to lines on the very top. Those cut outs have a load break on them them so when you open them under load they don't arc. That's what the flag shaped thing is on them.
Stuff around here that looks like that is automatically/remotely switched power factor correction equipment.
They installed some that look almost exactly like that a mile from my house I pulled up to the crew and asked if it was power factor correction equipment they were installing and their answer was "are you looking for a lineman job?".
They installed some that look almost exactly like that a mile from my house I pulled up to the crew and asked if it was power factor correction equipment they were installing and their answer was "are you looking for a lineman job?".
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The capacitors (rectangular boxes) are sparingly used to correct curreny lag when there are too many induction devices (motors) being powered thereby causing the current to lag (peak occure after) the voltage. As more induction devices are being powered the current lags more. The current lagging the voltage is called the power factor. The real available power decreases if the current lag gets too bad. If the powerfactor is too bad then the capacators are tied in to correct it back to not be as bad. The reason the capacitors are sparingly used is because they are expensive and have a limited number of use hours.
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they're current transformers (CT) or potential transformers (PT), could be both. in the transmission world I've never seen them on the line. they are always in the station.
the current breakers are completely different they are rectangular for lower voltages and cylindrical with pressurized hexafluoride on the high side. we've also started building them more in a shop as a unit setting everything in one piece on site. I just did a tie in for 345kv collector station and its no bigger than an old school typical 138kv station from 30 years ago.
I’m curious what your thoughts are. We have something like this down the road from us with a giant transfer switch. I don’t know the specifics.. only what my retiree neighbor told me who talked to the guys when it was put in.
I assumed they were to step down voltage for the transfer switch’s system. No idea why it has 4+ transformers though.
Those are capacitors .
