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Discussion Starter · #1 ·
Those of you who have been here a while (or new guys who do a search) know that I had no love for my old POCO in Southern California....between aged equipment and crews who don't give a damn about customer service they had a lot of problems. The latest one was the 36-hour outage right before I moved. Prior to that was the burned crossarm incident that had an 8-hour or so outage.

By contrast, the POCO in my new home's region (Idaho Power) shows how it is supposed to be done.

We had an outage a few days ago...system reclosed once then locked out. On my way to town on the "old road" (our power's ROW is there) found a phase laying on the burned crossarm. I had already called in the outage, but called again to let them know where this damage was at. They thanked me for the info and relayed the info to the crew.

A mere few minutes after that call I saw a crew heading toward me, I flagged them down and relayed the info to them...they thanked me as well.

I ran into town to run my errands, by the time I got done (about an hour) I was heading back up the road and saw the crew wrapping up the repair. :eek::thumbup:

Spent some time chatting with them as the reclosed the line and got the power back up. :thumbup:

Total outage time? Under 3 hours start to finish.

Cause: Failed new-school "plastic" insulator that tracked badly during the rain that day. (like one of the others on the same crossarm, to be fair it was most likely damaged by shotgun shot before it tracked. I have the third, undamaged insulator from that same arm.) They replaced the plastic ones with porcelain ones.

Not bad for a "rural" POCO.

What made the difference? Well:


  • Dispatchers who knew what an electrical power distribution system is, not some dumb betty who barely knows what electricity is;
  • Repair crews that actually carry such basics as spare crossarms and insulators ON THIER TRUCK, not crews who have to run back to the yard for every little thing;
  • Crews that assess the damage, have a quick tailboard and set to working on the repair, not crews who BS for an hour and finally lope into getting the repair done;
  • And an unrelated factor, but they also use wye distribution with a hard wire neutral and grounds on virtually every pole, not the ungrounded delta that SCE had such a hard-on for.
Bonus: my electric rates are cheaper here too. :)
 

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Homer to Jebus
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Rocky Mountain Power is the same way. Someone knocked a transformer out with a snow plow, called them up and a new one was installed in 4 hours. :thumbsup:
 

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I've lived in SoCal for 13 years in Fullerton and Anaheim with SoCal Edison as my utility and
Besides high rates I've never really lost power. Maybe once a year for 5 minutes. And I had my old a service drop replaced to a triplex with one phone call. Also most of the guys I see in the field seem to be alright. Now Detroit Edison crews are pos.
 

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Fond of three phase
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I've lived in SoCal for 13 years in Fullerton and Anaheim with SoCal Edison as my utility and
Besides high rates I've never really lost power. Maybe once a year for 5 minutes. And I had my old a service drop replaced to a triplex with one phone call. Also most of the guys I see in the field seem to be alright. Now Detroit Edison crews are pos.
Doesn't Detroit Edison furnish a bullet-proof vest, as part of their crew's PPE. :rolleyes:
 

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Discussion Starter · #5 ·
Rocky Mountain Power is the same way. Someone knocked a transformer out with a snow plow, called them up and a new one was installed in 4 hours. :thumbsup:
Yeah I heard from others around here that they are really efficient too. (I am just outside of RMP's service area.)

I've lived in SoCal for 13 years in Fullerton and Anaheim with SoCal Edison as my utility and
Besides high rates I've never really lost power. Maybe once a year for 5 minutes. And I had my old a service drop replaced to a triplex with one phone call. Also most of the guys I see in the field seem to be alright. Now Detroit Edison crews are pos.
In Hawthorne I went over ten years without any issues, then suddenly all hell broke loose with several outages in just a few years, with the two major ones I mentioned only months apart.

A fair number of the crews I spoke with were ok, but they definitely were not in any way motivated to work with even a slight sense of urgency. It may have been a regional thing within SCE, the Southbay crews may be of a different mindset than the crews in Orange County/Inland LA county.
 

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like a hawk, ive been keeping my eye out for apprentice opportunities with both idaho power and pacificorp.......i would LOVE to get onboard with either company =)
 

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Discussion Starter · #8 ·
What happened to the guy who posted this?:

12-20-2013, 02:03 PM #50 MTW
Senior Member

Join Date: Aug 2013
Location: Northeast USA
Posts: 2,724



I can't believe I'm about to say this, but........maybe Mxslick isn't being so dramatic about SCE after all. That's some pretty neglected equipment right there. :eek:
The Following 2 Users Say Thank You to MTW For This Useful Post:
Remove Your Thanks meadow (12-20-2013), mxslick (12-20-2013)
On this thread: http://www.electriciantalk.com/f2/oops-sce-did-again-63430/index3/
 

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In Vermont we've had a major acquisition by GMP (Green Mountain Power) that saw our major poco CVPS (Central Vermont Public Service) vanish

Inasmuch as it's the same 'ol REP era infrastructure, the dif in customer service has been phenomenal

That's kinda nice if you've gotta deal with 'em day in/out:thumbsup:

~CS~
 

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Those of you who have been here a while (or new guys who do a search) know that I had no love for my old POCO in Southern California....between aged equipment and crews who don't give a damn about customer service they had a lot of problems. The latest one was the 36-hour outage right before I moved. Prior to that was the burned crossarm incident that had an 8-hour or so outage.

By contrast, the POCO in my new home's region (Idaho Power) shows how it is supposed to be done.

We had an outage a few days ago...system reclosed once then locked out. On my way to town on the "old road" (our power's ROW is there) found a phase laying on the burned crossarm. I had already called in the outage, but called again to let them know where this damage was at. They thanked me for the info and relayed the info to the crew.

A mere few minutes after that call I saw a crew heading toward me, I flagged them down and relayed the info to them...they thanked me as well.

I ran into town to run my errands, by the time I got done (about an hour) I was heading back up the road and saw the crew wrapping up the repair. :eek::thumbup:

Spent some time chatting with them as the reclosed the line and got the power back up. :thumbup:

Total outage time? Under 3 hours start to finish.

Cause: Failed new-school "plastic" insulator that tracked badly during the rain that day. (like one of the others on the same crossarm, to be fair it was most likely damaged by shotgun shot before it tracked. I have the third, undamaged insulator from that same arm.) They replaced the plastic ones with porcelain ones.

Not bad for a "rural" POCO.

What made the difference? Well:


  • Dispatchers who knew what an electrical power distribution system is, not some dumb betty who barely knows what electricity is;
  • Repair crews that actually carry such basics as spare crossarms and insulators ON THIER TRUCK, not crews who have to run back to the yard for every little thing;
  • Crews that assess the damage, have a quick tailboard and set to working on the repair, not crews who BS for an hour and finally lope into getting the repair done;
  • And an unrelated factor, but they also use wye distribution with a hard wire neutral and grounds on virtually every pole, not the ungrounded delta that SCE had such a hard-on for.
Bonus: my electric rates are cheaper here too. :)
Sounds like a match made truly in Heaven.
 
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Those of you who have been here a while (or new guys who do a search) know that I had no love for my old POCO in Southern California....between aged equipment and crews who don't give a damn about customer service they had a lot of problems. The latest one was the 36-hour outage right before I moved. Prior to that was the burned crossarm incident that had an 8-hour or so outage.

By contrast, the POCO in my new home's region (Idaho Power) shows how it is supposed to be done.

We had an outage a few days ago...system reclosed once then locked out. On my way to town on the "old road" (our power's ROW is there) found a phase laying on the burned crossarm. I had already called in the outage, but called again to let them know where this damage was at. They thanked me for the info and relayed the info to the crew.

A mere few minutes after that call I saw a crew heading toward me, I flagged them down and relayed the info to them...they thanked me as well.

I ran into town to run my errands, by the time I got done (about an hour) I was heading back up the road and saw the crew wrapping up the repair.

Spent some time chatting with them as the reclosed the line and got the power back up.

Total outage time? Under 3 hours start to finish.

Cause: Failed new-school "plastic" insulator that tracked badly during the rain that day. (like one of the others on the same crossarm, to be fair it was most likely damaged by shotgun shot before it tracked. I have the third, undamaged insulator from that same arm.) They replaced the plastic ones with porcelain ones.

Not bad for a "rural" POCO.

What made the difference? Well:


  • Dispatchers who knew what an electrical power distribution system is, not some dumb betty who barely knows what electricity is;
  • Repair crews that actually carry such basics as spare crossarms and insulators ON THIER TRUCK, not crews who have to run back to the yard for every little thing;
  • Crews that assess the damage, have a quick tailboard and set to working on the repair, not crews who BS for an hour and finally lope into getting the repair done;
  • And an unrelated factor, but they also use wye distribution with a hard wire neutral and grounds on virtually every pole, not the ungrounded delta that SCE had such a hard-on for.
Bonus: my electric rates are cheaper here too. :)
:thumbup:

You met a worthy poco! Its nice to see them listening to you and respecting you being a customer. :yes:

Tell them unless your using tree wire or spacer cable epoxy insulators are over rated. Never, ever use rubber tie downs on anything, they break like no tomorrow. Vise tops aren't the best for bare wire since the wire tends to slide through it when a pole or tree comes down. Good ole porcelain pole with steal tie downs still win hands down.


By the sounds of it they know protective relaying well. The cross arm was actually in one piece when the recloser locked out:laughing::laughing: I have seen conductors slide out of con ed insulators with the phase arcing for some time until it burns through the cross arm. Falls through hitting the neutral; line recloser will make 4 hard auto reclose attempts in that condition. Lights take their time staying dim, I swear they mustve been trying to clear the fault via buss bar burn through.

In your case since your line is rural so don't worry about one auto reclose attempt, that's usually sufficient. A lot of distribution engineers fail to realize 4 attempt options are provided more for bare wire construction coordinating with trip count sectionalizers or fuse saving schemes.



"And an unrelated factor, but they also use wye distribution with a hard wire neutral and grounds on virtually every pole, not the ungrounded delta that SCE had such a hard-on for."

I thought the 4.6kv system serving your apartment was an isolated neutral wye? At least it looked like that. Unless you referring to the 3 wire 16kv circuits. As for the SCEs phase to phase hard all California utilities are required to follow PUC 95 which has rules against using the grounding system as a neutral similar to the NEC rules. As a result California utilities are required to connect transformers phase to phase or to treat the neutral like a live phase keeping it isolated on insulators while keeping neutral ground bonds at a minimum after the supply substation. Sounds crazy but its something to be thankful for. Im not a fan of Multi grounded neutral distribution for reason I don't want to get into.



"I have the third, undamaged insulator from that same arm.) They replaced the plastic ones with porcelain ones." Pics or it didn't happen:whistling2::jester:



Best of luck MX. Sorry about the delay but was busy.
 

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Discussion Starter · #14 ·
:thumbup:

You met a worthy poco! Its nice to see them listening to you and respecting you being a customer. :yes:

Tell them unless your using tree wire or spacer cable epoxy insulators are over rated. Never, ever use rubber tie downs on anything, they break like no tomorrow. Vise tops aren't the best for bare wire since the wire tends to slide through it when a pole or tree comes down. Good ole porcelain pole with steal tie downs still win hands down.


By the sounds of it they know protective relaying well. The cross arm was actually in one piece when the recloser locked out:laughing::laughing: I have seen conductors slide out of con ed insulators with the phase arcing for some time until it burns through the cross arm. Falls through hitting the neutral; line recloser will make 4 hard auto reclose attempts in that condition. Lights take their time staying dim, I swear they mustve been trying to clear the fault via buss bar burn through.

In your case since your line is rural so don't worry about one auto reclose attempt, that's usually sufficient. A lot of distribution engineers fail to realize 4 attempt options are provided more for bare wire construction coordinating with trip count sectionalizers or fuse saving schemes.



"And an unrelated factor, but they also use wye distribution with a hard wire neutral and grounds on virtually every pole, not the ungrounded delta that SCE had such a hard-on for."

I thought the 4.6kv system serving your apartment was an isolated neutral wye? At least it looked like that. Unless you referring to the 3 wire 16kv circuits. As for the SCEs phase to phase hard all California utilities are required to follow PUC 95 which has rules against using the grounding system as a neutral similar to the NEC rules. As a result California utilities are required to connect transformers phase to phase or to treat the neutral like a live phase keeping it isolated on insulators while keeping neutral ground bonds at a minimum after the supply substation. Sounds crazy but its something to be thankful for. Im not a fan of Multi grounded neutral distribution for reason I don't want to get into.



"I have the third, undamaged insulator from that same arm.) They replaced the plastic ones with porcelain ones." Pics or it didn't happen:whistling2::jester:



Best of luck MX. Sorry about the delay but was busy.
Thanks for the response, lots of good info there. :thumbup:

You're not mistaken, my old apt. was 4.6 wye. I was referring to the 16kv and 34.5 they use elsewhere.

Can you elaborate on why the MGN is something you're not fond of? I do know that SWER (Single Wire Earth Return for those who have no idear what we're babbling about) was in use here for may years, but has been converted into a MGN system as evidenced by the construction visible. As for SWER, that is something I always thought was a bad idea.

And I didn't take any pics of the damage or repair, I had a full schedule that day and probably shouldn't've wasted the time I did talking to the crews. I can get a pic of the insulator they gave me though, and if I can get back down the road I'll grab a pic of the new crossarm.
 

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I thought the 4.6kv system serving your apartment was an isolated neutral wye? At least it looked like that. Unless you referring to the 3 wire 16kv circuits. As for the SCEs phase to phase hard all California utilities are required to follow PUC 95 which has rules against using the grounding system as a neutral similar to the NEC rules. As a result California utilities are required to connect transformers phase to phase or to treat the neutral like a live phase keeping it isolated on insulators while keeping neutral ground bonds at a minimum after the supply substation. Sounds crazy but its something to be thankful for. Im not a fan of Multi grounded neutral distribution for reason I don't want to get into.
Is PUC 95 unique to California? I noticed the neutral conductors on insulators and always wondered why that was the case in my travels there.
 

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Discussion Starter · #18 ·
Is PUC 95 unique to California? I noticed the neutral conductors on insulators and always wondered why that was the case in my travels there.
I think they follow PUC 95 here as the MGN's are on insulators.
 

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Thanks for the response, lots of good info there.

You're not mistaken, my old apt. was 4.6 wye. I was referring to the 16kv and 34.5 they use elsewhere.

Can you elaborate on why the MGN is something you're not fond of? I do know that SWER (Single Wire Earth Return for those who have no idear what we're babbling about) was in use here for may years, but has been converted into a MGN system as evidenced by the construction visible. As for SWER, that is something I always thought was a bad idea.

And I didn't take any pics of the damage or repair, I had a full schedule that day and probably shouldn't've wasted the time I did talking to the crews. I can get a pic of the insulator they gave me though, and if I can get back down the road I'll grab a pic of the new crossarm.

I meant the insulators, not the repair. My bad.

I will try to keep it simple it, but any way, to the MGN aka TN-C earthing (combined neutral and ground). Its a step above SWER, but still has major, major issues. An MGN is no different then wiring a building without neutrals but with an egc system and using that as the neutral conductor as well as the EGC. Basically every load with a hot and the conduit used as both as a ground and neutral; or a hot and a bare wire at every load type deal. Bare wire goes to the N and jumps over to the frame as well. Will it work to some degree? yes. Will it save money? yes Safe? Not so much.



Major problems exist with MGNs or using a buildings ground wires for as a neutral.

1. Current will dived between the neutral and every metal object its grounded to more than once. Current will divide between the MGN and water pipes, telephone cable/cox shields, ground rods, gas lines, building steal and foundations, anywhere where a conductive path exits. This creates both EMFs (primarily magnetic) and stray voltage gradients which for some pocos are a major legal problem, which I will get to. Harmonic and none linear loads make the problem far worse since they drastically increase neutral current as well as unbalanced feeders from load growth. Years ago stray voltage was usually not a concern for pocos but its now becoming a huge and noticeable issue as the above increases as well as equipment ages.




2. A broken neutral will go unnoticed until it sets something on fire or stray voltage problems arise. When an MGN breaks, current will just be pushed over what it can find which is ground rods and metal piping. Even though an MGN is close to earth potential (thanks to its repeated grounding) its actually at thousands of volts potential between the loads and the source transformer. Those thousands of volts show up in some way or another. If a neutral breaks where it has poor parallel paths such as a neighborhood with plastic mains and no gas lines it gets noticed fast . Thousands of volts will heat up ground rods quick as well as producing lethal step touch potentials. No device will notice this or stop it. It has happened before where less parallel paths were available. Even then broken neutrals show up as people getting shocked on pluming and swimming pools, but those cases have also been noted on systems where the neutral is under sized/overloaded. Theoretically, a person could loose the mgn at a pole or pad mount, and their water bond will take the whole thing over unnoticed. What happens to the person who has to lift it or there isn't on?:eek:

3. Downed conductors often go unnoticed in MGN systems. Line reclosers and substation feeder breakers have to be set with a high ground trip/ high phase differential pick up values (think GFCI or RCD protection in LV systems) to allow for normal neutral loads. Often the values are 1/3 to 2/3 of the phase pickup value but values as high as the phase setting are not uncommon. Pick up values of 250 to 800amps where the phases are set at 1000amps is fine for detecting bolted faults such as a phase crashing into the neutral, but faults on soil, cross wooden/ungrounded cross arms, concrete, tree branches and the like frequently go unnoticed. Not all downed conductor or tree contact will generate enough current to reach these values, protective devices just see it as a heavy single phase to neutral load. As the conductor burns usually the current will go down even further from soil drying out. I have seen countless times including up my street during storms where a phase will fall into the road arcing into the asphalt until a line crew shows up to trip the recloser. Last time it took over an hour for them to get there. I think we all know why that's dangerous. However, where all loads are connected phase to phase or an isolated neutral that can be ct, values can be set only to a few amps. Conditions that generate less than a few amps are extremely rare, so nearly all downed conductor contingencies including wires across a sidewalk are cleared, as well as minimal carnage from what would normally be sustained undetected arcing in an MGN. Of note, Recloser and breaker makers are now offering "sensitive earth fault logic" for protective microprocessor relays which is nothing more than highly sophisticated AFCI protection. Most high impedance downed conductor conditions will show an arcing signature. In an mgn system the arcing signature can help in detecting downed conductor conditions that fall out of the normally set current pick up values. However, its expensive, and 2 its not always perfect as the good ole low RCD method of clearing high impedance faults. I know what your thinking MXSlick, but its light years ahead of standard AFCIs. Its done with high bit oscilliography analysis that's then run through a slew of software equations. Some of them can even guestimate how far out on the line the fault is. And yup, as a result no nuisance tripping :yes: And yes, you know why the damn thing tripped in the first place:thumbup::laughing:

4. Legal issues. Because MGNs produce 60hz voltage gradients across the earth its getting noticed. POCOs are being flooded with lawsuits from dairy farmers and property owners over step voltage potentials. As loads increase and equipment ages more and more people are noticing it. Google would better describe the issue but countless dairy farmers have gone out of business because of it. A few volts may not get noticed by humans, but a 4 legged animal will feel it. Cows not drinking from the trough is one reason since the animal will feel it and associate the water trough as discomfort. Mike Holt actually some good videos on the subject. Property owners are also suing where its really bad because swimming pools and pipes are shocking. Up in Minnesota a utility actually had to change one of their rural systems over to a delta because of so many dairy farmers suing. Others all over the US are installing ronk blockers to mitigate the problem. Trust me some pocos are regretting the MGN system.


Another legal issue for pocos has been people getting killed in pools and lakes from deteriorated bare concentric neutral cables. Years ago when pocos started putting residential sub divisions under ground they had a thing for bare concentric neutral cables. EPR or XLPE with a bare concentric aluminum braid, its no different from the one around SEU cable, just it has no covering. Kind of like sticking SEU in the ground with no jacket. As these cables deteriorate, the HV neutral current ends up going through water pipes and the earth. As a result dangerous voltage gradients are occurring across the earth. Energized metal water pipes too as being noted. Such issues however in California are rare, and Dairy farmers suing pocos is unheard of. I wonder why?

5. EMFs. MGN systems can and do give rise to major magnetic fields. Both power lines have higher EMFs as well as anywhere the neutral current is flowing. Power lines give off higher magnetic fields since current cant cancel. 50 amps flowing on a phase ends up as about 25 amps o the neutral and 25 amps over what else. The 25 amps that don't cancel show as excessive EMFs from the line as well as the metal water piping in the street, building steal or anywhere else that current is flowing. Believe it or not magnetic fields in residential neighborhoods are often much higher than main roads holding trunk lines since ground current wont cancel. 3 phase main lines hold predominantly 3 phase banks, and where single phase banks are present what phase they are connected to rotates down the line. Pole 1 has a 50kva pig pulling 10 amps on a phase, pole a few yards down with a pig of 11amp on b, pig pulling 12 on c phase again a few yards down. Net neutral current is about 1.7 amps up the line with 11 amps only between the pigs. However on a single phase lateral, current will add, 10+11+12 to 33 amps plus all the other pigs on the line. A single phase trunk can easily see 100 amps or more. Often over half that amount is being pushed into the earth via ground rods and water bonds. Add to the fact the HV neutral also doubles as the LV neutral and even more current winds up where it shouldn't.

Yes its debatable what EMFs actually do, but considering the US has some of the highest cancer rates in the world (among other conditions) where this system is by far the most prevalent in use, shouldn't be ruled out as a potential contributing factor that needs real investigation. Even if it is proven magnetic fields are a potential risk (some already have) pocos will never admit their systems are an issue since overnight they would be opened up to potential lawsuits. Just trust me on the fact when I say its a good thing California has crazy laws in place.


MGN systems are extremely rare outside the US and Canada. 3 phase 3 wire is the norm through out the world. In some areas MGNs are even forbidden on the LV systems.


Long info rant but I think you get the picture. Anyway, MX I wouldn't worry about your distribution system. Being a rural line I doubt its caring much load as is, and being a top poco I doubt its the system is in a neglected state. :)

If I'm not mistaken, I think meadow is in favor of an isolated neutral rather than an MGN system.
Yup. Or just connecting loads phase to phase, which ever gets the job done. Phase to phase tends to (but not all the time) be the preferred choice since it often comes out cheaper to buy a fully insulated transformer then to run the neutral, plus there is no concern of neutral shift or the infamous open neutral.


Is PUC 95 unique to California? I noticed the neutral conductors on insulators and always wondered why that was the case in my travels there.
Puc is unique to California. California utilities will connect transformers phase to phase or to an isolated neutral. Its treated as a phase and in most case only grounded down at the substation. And when it opens up it gets noticed:thumbup::eek:




I think they follow PUC 95 here as the MGN's are on insulators.

I doubt it. If its an MGN its not following PUC:tt2: If the neutral has any connections to ground rods or jumpers over to the LV neutral its not an isolated neutral even if on insulators. Some pocos do actually put the MGNs on insulators (usually 600v rated spools) but not with the intention to electrically insulate but rather to prevent aluminum wiring from touching dissimilar metals.
 
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