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I go to lineman school in 4 days, and they mentioned something abouts substation work, what are the duties of a substation electrician, and how do you gdt to that level of work? Is it later on in the career or is it a job you have to go to a different linework school for?
 
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All of the substation guys i have worked with started out as lineman. Basically you have to learn control wiring, troubleshooting, pm's and how to move heavy equipment in a tight dangerous area.
 

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I got substation work as a journeyman electrician - without prior experience - because I had an industrial first-aid certificate. It happened to be where the union dispatch sent me.
 

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Seems it would be where most guys would want to be? Maybe out of the weather? Maybe a bit more complicated? I'm not exactly sure what the job is, but I think I would prefer that to being on a pole in the snow or rain and working far from home. Seems like it could be the best place to be?
 

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Substation work is dangerous.....when I first started I worked at PECO in substations changing out breakers and protective relays for maintenance....substations are all a little different and as I found out most of the safety procedures are developed after electrical accidents......to learn what to do so you don't get killed, you need to work with someone who knows that particular substation......one of the most dangerous things we routinely did was after we removed Medium voltage breaker....(Following written procedures) I would lay on my back in the cubical and measure with voltage with phasing sticks before we racked the new breaker...this was the way it was done until someone got their face melted...
 

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Friend of the family was a FPL meter reader and was among the positions which got eliminated by smart meters. They sent him to substation electrician school and that's what he's been doing for more than ten years now. He never was a lineman.

I'm sure every organization has their own way of doing things.
 

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I’m a substation electrician. We build and maintain everything within the substation fence. That includes breakers, PTs, CTs, transformers, capacitor banks, regulators, various types of air switches and disconnects, all of the bussing, everything inside the panel house, pulling cable, wiring, using heavy equipment, bucket trucks, manlifts, crane trucks. I’m sure there’s more but that’s the jist of it just off the top of my head. It’s a fun job. I’m not sure if there’s a separate school for it but a lot of the guys I work with came from the line side and a lot of the guys didn’t. Some even had no prior electrical experience. The utility I work for has a 4 year apprenticeship for substation construction and maintenance and you learn everything you need to know. I can answer any questions you have if you’re interested.
 

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Why hasn't anyone mentioned to the lad, sub-stations involve very high voltages.
Worked in a MCC with motor starters running 4160 volt motors.
Was not comfortable around those voltages.
I'll keep to the wimpy 480 volt stuff.
 

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Why hasn't anyone mentioned to the lad, sub-stations involve very high voltages.
Worked in a MCC with motor starters running 4160 volt motors.
Was not comfortable around those voltages.
I'll keep to the wimpy 480 volt stuff.
Did you see the thread where he built his own 7.2KV transformer and miniature powering? I think he knows.

Sent from my SM-G970U using Tapatalk
 

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I’m unaware of any substations that involve MCCs and motor starters. The dangerously high voltages are all in the overhead bus ...13.8, 115, and 230kv. Everything down low is either 125 DC or 120/240 AC which are both used to control various pieces of equipment (circuit breakers and panel house lights/heaters, etc). Are you in the USA wiz? What application were you working in that involved MCCs and motors?
 

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I’m unaware of any substations that involve MCCs and motor starters. The dangerously high voltages are all in the overhead bus ...13.8, 115, and 230kv. Everything down low is either 125 DC or 120/240 AC which are both used to control various pieces of equipment (circuit breakers and panel house lights/heaters, etc). Are you in the USA wiz? What application were you working in that involved MCCs and motors?
May not have the same terminology as you linemen.
I was working in chemical plants and refineries on the Houston Ship Channel.
The sub-station is what we called the incoming power building that fed several MCC's.
Some of the starters were 4160 for 700 horsepower compressors used to compress propane.
Did not like being in the MCC when one of those came on.
 

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5kv is just the beginning. There are fresh water plants near me that have 15kv equipment, starters and breakers. Large vertical pumps, 2000 horse power .
I showed up and my fore person explained that we would be pulling the equipment one cell at a time, hot. Like he double hockey sticks. Called the boss and he showed up, looked at the miles of gear and said guess we need an outage, duh! More than willing to crawl in and do rags and dirt inspections with the buss off and grounded.
Granted these buildings are not inside the fence for the substation proper, but the substation has the breakers feeding these buildings at 15kv.
 

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Discussion Starter #15
I’m a substation electrician. We build and maintain everything within the substation fence. That includes breakers, PTs, CTs, transformers, capacitor banks, regulators, various types of air switches and disconnects, all of the bussing, everything inside the panel house, pulling cable, wiring, using heavy equipment, bucket trucks, manlifts, crane trucks. I’m sure there’s more but that’s the jist of it just off the top of my head. It’s a fun job. I’m not sure if there’s a separate school for it but a lot of the guys I work with came from the line side and a lot of the guys didn’t. Some even had no prior electrical experience. The utility I work for has a 4 year apprenticeship for substation construction and maintenance and you learn everything you need to know. I can answer any questions you have if you’re interested.
I have lots of questions lol
 

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I’m unaware of any substations that involve MCCs and motor starters. The dangerously high voltages are all in the overhead bus ...13.8, 115, and 230kv. Everything down low is either 125 DC or 120/240 AC which are both used to control various pieces of equipment (circuit breakers and panel house lights/heaters, etc). Are you in the USA wiz? What application were you working in that involved MCCs and motors?
Things have changed. Overhead subs with tubular bus are not popular anymore. Up to 35 kV most of it is going to indoor/enclosed, underground, etc. Just far fewer issues with it. Above 35 kV (sub transmission and transmission lines) obviously everything is overhead and runs to bushings with LV controls. Depending on where you are I’ve even seen higher pressure GIS used for space reasons running 69 kV SF6 breakers or VCBs under 40 kV with gas insulated bus. Fort LeJeune for instance uses this stuff in portable subs for its incredibly rugged nature.

So specifically for MCC...

MCC is typically used for motor controls. You can get it rated to 65 kA AIC but you’ll pay for it. 35 kA or less is more typical. I don’t usually see it anywhere in a utility distribution substation because the few motors involved are typically just industrial control panels such as sump pumps, fuel pumps, fans, compressors where old air over springs are used. Industrial and power plant subs are another story because the motor/station bus is often integrated with the switchgear in the same building with only the transformers, GSUs, etc., external. These are “internal” subs of course...the GSU sub yard at a utility is going to be fed MV but then quickly step up to EHV.

I used to work for a large industrial operation where we built about a dozen substations a year. So I’ve seen a lot of different combinations. Even among utilities each one has their own variations.
 

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I see. I understand how it may vary on location. The utility I work for has 200 subs varying from 230, 115, and 13.8 and they are all above ground with overhead conductors even the brand new subs. I live in the northwest with very rocky soil so underground may not be an option. Also since the OP was talking about being a lineman and a substation tech I figured he was asking about transmission and distribution subs since they go hand in hand with line work, rather than privately owned industrial subs where you would encounter MCCs, pumps and motors. We do have some of those at mills and mines in the area but those are all operated privately by the employees of those companies. OP if I’m correct in assuming you’re asking about the substations/switch yards that the power lines you’re working on feed in to... post up your questions
 

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Discussion Starter #18
I see. I understand how it may vary on location. The utility I work for has 200 subs varying from 230, 115, and 13.8 and they are all above ground with overhead conductors even the brand new subs. I live in the northwest with very rocky soil so underground may not be an option. Also since the OP was talking about being a lineman and a substation tech I figured he was asking about transmission and distribution subs since they go hand in hand with line work, rather than privately owned industrial subs where you would encounter MCCs, pumps and motors. We do have some of those at mills and mines in the area but those are all operated privately by the employees of those companies. OP if I’m correct in assuming you’re asking about the substations/switch yards that the power lines you’re working on feed in to... post up your questions
Yes, im talking about the subs and switch yards for the transmission lines, sub trans and distribution lines feed into, now the area that ill be working in. Southeastern ohio (so AEP) has several backbone 765kV and 500kV lines in my area, and the rest are 138kV or old 69kV lines, we have about 7 subs and switch yards for the 765 going through this region, and then a crapload of 138 and 69 subs, now rarely see sub techs go into the switch yard down the road for the 765, what is routine maintenance like. And do the transformers automatically switch on or do you manually do it? And what is the overall procedure of maintaining a sub? I've seen workers do a change out of a 345kv circuit breaker but how do the keep the power on without using a mobile sub? Do they have a tie switch? Is that why most subs have two transformers, 2 sets of busswork, and generally 2 of everything?
 

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Transformers do not automatically switch on. They are always energized unless there is an internal fault on the transformer and then a crew will come open some air switches to isolate it from the system and then it can be investigated. There are a thing called autotransformers but that’s referring to the transformer changing taps and adjusting its voltage according to support the load at any given time. Every air switch in the sub must be operated by a person. Nothing switches in or off automatically except for the opening of the breakers under a fault condition. All breakers can be remotely controlled via SCADA but that’s another topic. Substation maintenance includes: doing maintenance on the breaker itself...testing the condition of the insulating medium of the breaker (oil, gas, etc), checking the contact wear of the breaker, measuring resistance across the closed contacts of each phase, doing power factor tests on all the PTs, doing the same tests on capacitor banks and regulators if the sub has them, there may be more but it’s 4 am where I am right now. That’s for planned maintenance. If any condition arises which is noticed by SCADA then a crew will come out and do perform a megger or TTR test and replace whatever needs to be replaced. That’s the basic jist of maintenance, each utility may be different but they all do circuit breaker maintenance. There are different bus configurations that allow any one circuit breaker to be de-energized for maintenance/repairs/replacement or whatever without losing the load for the line that breaker is tied into. Double breaker double bus, breaker and a half, aux bus, ring bus, etc. you can look up these terms to see more about them if you want. The load can be switched through various different subs and switch yards in emergency or planned outages if need be like in a big storm or whatever. The system operator who sits in an office and has a view of the overall system and control of the whole system can see how everything is tied together and if a line goes out in an emergency can still find a way to supply load to the customer via a different substation. The system operator has remote control of every breaker via SCADA (supervisory control and data acquisition, basically remote control over everything, and can see the power flowing through each sub, different alarms associated with each sub, etc). In my utility we build the subs and do upgrades which is my favorite part..:replacing breakers, PTs, regulators, hanging bus, etc basically anything that needs to be replaced. Or just building an entire sub from the ground up. Each utility may be different in that aspect. I hope I answered some of your questions let me know if I missed anything
 

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Chief Flunky
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Mines often use portable subs. 2-4 large 12” or larger W’s welded into a grid to make a frame then everything mounted on that so that they can gently move it with a large dozer. What’s on top is a typical indoor sub.

Indoor style gear is just that. Everything is in a duct. Only the incoming bushings are exposed or in their own compartment. Bus is isolated in the back. Draw out gear except GIS which is basically once and done since you can’t take anything apart. This works up to 35 kV. A variation uses elbow connectors and puts everything into a vault. For instance everything in Charleston, SC is this way. The water table there is like 12” below grade. You can’t get to anything without first pumping out the vault. All their subs are effectively underwater. Some other utilities like the “vault wiring” style like where everything goes on a pad with the wiring buried below it. I’m not really a fan. If you’ve ever had to troubleshoot or repair anything buried you will know why. But it does stay out of harms way better. Here in Atlantic hurricane alley the all underground utilities have very little storm damage.
 
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