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lightman
06-16-2013, 08:02 PM
I got a call at 06:30 yesterday with a circuit out. We just started taking calls in a larger area, so while familiar with it, was not my regular area. Drove for 30 minutes to get there, and found a phase burned down, right outside the substation. It burned into at a buckarm corner, at a connection. Was not even on the ground. After all of the switching, tagging, and grounding, it was not a really big job to pick it up. While not being sure if a connection had failed or maybe a fault downstream had caused it, I looked at the rest of the circuit, up to the next device, before switching it back on.

Now is where the fun starts! Since it happened early, lots of customers left home for work, or whatever. I continued to get calls all day, turning out to be just late calls. Like about five or six. The last call that I got was an elderly lady, and when I arrived, found a generator running. She was way out in the rural, and I checked all of the devices and line switches along the way. Finding nothing wrong, I arrived at her house, to find the display on her meter lit up. A voltage check showed the power to be on. I talked with her, and she said she was still off. I move the handle on the transfer to switch to utility and killed her generator and ask her to look in the house. While she was gone, I checked the voltage once again. She came back out and said that they just came back on. I told her that she had been back on since early morning,, but she disagree. I wished her a happy evening and drove away. When I called the dispatcher to report in, I had to wait until I quit laughing to talk with him. I was too tired to get mad. Before I went out, I ask the dispatcher to call her. She reported hearing a loud boom and the lights went out! Well duh! The life of a serviceman! Lightman

PHASE2PHASE
06-18-2013, 01:02 PM
You gotta love those hours late calls. I had a substation breaker locked out yesterday too.
Dispatch said I had BI and CI targets on the relays. The feeder goes underground out of the sub, OH across the highway and tees off. I patrolled both ways to the first set of reclosers, one set of single phase hydraulics and one ABB and everything looked good. Tested breaker and underground, everything good. Made the line back hot and it held. I thought maybe a pelican went ph 2 ph but found nothing. Got a call a few minutes later of a tree on the line. About a mile downstream of the ABB a big, rotten pine had fallen across B, C and the neutral and broken off above the neutral and B and C were back in the clear. The tree had the neutral and CATV mashed down to eye level. The ABB didn't operate and the substation breaker saw the fault and opened. Does anybody else have problems with ABBs? We say it stands for "Another Bad Breaker".

HiStrung
07-02-2013, 09:26 PM
Below is three different devices ABB makes. Yours is probably the last.
I am familiar with the ABB AutoLink. They are the sectionalizer you can use in a cutout, instead of the fuse. They can get bent if you drop them from your switch-stick. If they get bent, then they won't repond appropriately. I don't think you are referring to an AutoLink.
We do have ABB R-Mag breakers. They are the three-phase breaker designed for substations. We had an electronic board go bad in one of those... otherwise I like their simplicity (S&C FVR breakers are more complex). The ABB R-Mag is an electro-magnet. If you get enough current to pass through a CT on the phase, then the control sends a trip cammand (130 volts DC) to the electro magnet. When you energize the electro-magnet, it pulls open the contacts in the vaccum bottle.
ABB also makes an OVR (Outdoor Vaccum Recloser). I bet this is what you are talking about. I don't know anything about them, because we don't have any, but I can speculate how they work. Most mechanical stuff work similar. Here are a couple ideas:
1) Does the control have power? The control power could be a battery or an auxillary tranformer.
2) Is the coordination on the system correct? This is the one I like. Every recloser has a TCC (time-current-curve). When you program devices, you can shift the curve up and down or side-to-side on the scale. Just because a device is set for a lower amperage, doesn't necessarily means it will trip faster. The two devices needs to have their TCCs separated by several cycles.
3) Mecanical malfunction/Another Bad Breaker