I may have to shut off a 2000A GFP main breaker on a 480V service to do some work, and I am a little nervous about having trouble getting it to reset, mainly because it looks old, and like it hasn't been touched in a few decades. Anybody ever have trouble with something like this? I plan to kill all the downstream panels, then the main, then vice versa on power up.
Main breaker shut off
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Good plan on your sequence of events.
As for that main:
As for that main:
- Good luck.
- Pray
- Wear FULL PPE on both shutoff and reset
- Pray again.
- If it does reset without blowing up or dropping a phase, go out and get drunk to celebrate your success.:laughing:
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We do this every day, I have opened four today (bolted pressure switches)?
As noted were PPE follow standard safety procedures
What type of Circuit breaker?
The GFPE should not make a difference.
Is there an GFPE test button-easiest way to open the CB
If you are adding any thing I would Megger before re-energizing
As noted were PPE follow standard safety procedures
What type of Circuit breaker?
The GFPE should not make a difference.
Is there an GFPE test button-easiest way to open the CB
If you are adding any thing I would Megger before re-energizing
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In situations like this, we would do whatever we could to avoid shutting off the main. Such as having the PoCo pull the cut-outs. If we had to shut it off, we would do whatever is necessary to be prepared for it to not go back on.
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You guys need my phone number.....
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We do this quite a lot.
Your sequence of shut-down is sound.
When you throw that 2000 back on line, make sure it has minimum load (as you know). Dont try to rig anything up, it just causes trouble.
Use your Cresent wrench, cycle all the way to off, and pull it in.
I wont even wish you good luck, because you will not have any bad.
Your sequence of shut-down is sound.
When you throw that 2000 back on line, make sure it has minimum load (as you know). Dont try to rig anything up, it just causes trouble.
Use your Cresent wrench, cycle all the way to off, and pull it in.
I wont even wish you good luck, because you will not have any bad.
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:blink::blink::blink::blink::blink:Cresent wrench?
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What is the model of the breaker?
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Get everything off the nameplate, even if you don't know what it means.
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So here's a concept:
If your breaker were to actually TRIP, and you found the downstream problem and corrected it, would you then be afraid to re-energize that breaker because "in might not turn on"? Wouldn't you want to KNOW if it was OK or not? If so, then wouldn't it make sense to learn that during a SCHEDULED shutdown like what you are about to do?
So to that point, if it DOESN'T reset, then what are the consequences? You have to replace it? Wouldn't you rather have to do that NOW when you knew in advance that you have to be shut down, as opposed finding out when your hair is on fire from managers screaming at you to re-energize after a trip?
I would call around in advance to see where you can find a replacement in a hurry if there is a problem, just to be prepared. You don't necessarily have to buy it (although the concept of "critical spares" comes to mind if this is such a big problem). Then you can look like a hero if it fails to reset and you can tell your boss "Yeah, that can happen, but XYZ Supply has one on the shelf, I can get it here tomorrow."
If your breaker were to actually TRIP, and you found the downstream problem and corrected it, would you then be afraid to re-energize that breaker because "in might not turn on"? Wouldn't you want to KNOW if it was OK or not? If so, then wouldn't it make sense to learn that during a SCHEDULED shutdown like what you are about to do?
So to that point, if it DOESN'T reset, then what are the consequences? You have to replace it? Wouldn't you rather have to do that NOW when you knew in advance that you have to be shut down, as opposed finding out when your hair is on fire from managers screaming at you to re-energize after a trip?
I would call around in advance to see where you can find a replacement in a hurry if there is a problem, just to be prepared. You don't necessarily have to buy it (although the concept of "critical spares" comes to mind if this is such a big problem). Then you can look like a hero if it fails to reset and you can tell your boss "Yeah, that can happen, but XYZ Supply has one on the shelf, I can get it here tomorrow."
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I never understood plants that have one main breaker, don't PM it ever, and don't have a spare in case something happens. How much per hour does it cost to have manufacturing down and employees standing around in the dark?
Yeah I have everything and can put a breaker on our company jet to get it to you in a few hours but that gets super expensive (Happens sometimes though)
Yeah I have everything and can put a breaker on our company jet to get it to you in a few hours but that gets super expensive (Happens sometimes though)
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We do critical spares analysis for people (not me, but our company). The horror stories I hear from our people about how short sighted managers can get have immunized me from shock any more. The common story is "it's too expensive". Somehow in business school, they fail to teach managers the TRUE cost of doing business; that an important factor to consider is what it will cost to be paying your entire workforce to do diddly squat while waiting for a critical part to arrive.
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It only took two major outages at a plastic injection molding shop here in town for me to convince them to hire a qualified contractor to start a PM program in their facility... I got the same look :blink: as Jlarson when I asked when the last time their electrical distribution had been tested and any PM had been done.
Pete
Pete
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Have a facility now, Medium voltage to 480/277 Main-Tie-Main, the 480 VAC bolted pressure switches are having closing problems and they have to remove the cover to manually pull up a latching mechanism to get the switch closed.
The operate on an A or B system and often have to switch back and forth between the Mains.
I asked when the last time they had maintenance and was told we do not need maintenance as we do IR every year.:blink:
The operate on an A or B system and often have to switch back and forth between the Mains.I asked when the last time they had maintenance and was told we do not need maintenance as we do IR every year.:blink:
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The looks we get at 2:00AM in the morning where are your spare fuses?
And during EPM's we always mention they should have spares on hand
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Best one I got recently: "We closed the switch and saw a huge flash, but management still wants to run so we're gonna try it again and call you back."
:blink: Don't even worry about calling me, 9-1-1 takes priority.
And OP, you either need a backup plan if the breaker fails, and/or you need to make it crystal clear (like in writing) that their is a legitimate chance the facility will not go back online after that breaker is opened, and let the customer make their own decision.
:blink: Don't even worry about calling me, 9-1-1 takes priority.
And OP, you either need a backup plan if the breaker fails, and/or you need to make it crystal clear (like in writing) that their is a legitimate chance the facility will not go back online after that breaker is opened, and let the customer make their own decision.
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