Line side

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engelectric

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Can u tap off line side of breaker ? I have a 800 amp main breaker want to add a 200 amp 3 phase panel add
Meter . Inspector said no , there is another set up next to another 800 amp that has what I want to do ?
 
Tapping directly from breaker terminals may not be acceptable if there is not sufficient lugs for all the conductors that will land there, but you can tap the conductors with separate means ahead of the breaker.

Are you tapping from feeder or service conductors?

Can the feeder or service handle the added load?

Are the supply conductors heavy enough for the added load?

If tapping service conductors, how many service disconnecting means are already existing?

You may be able to tap you may not, there are more questions that need answered first.
 
Here what exist , transformer 150 kva parallel feeder to two 800 amp 3 phase breaker each 800 amp has 6
Meter total plug in . The power company doing testing to see what other added load Can be added. If I understand you can add to breaker but only if there are twin port on top of breaker to land the wires, but can u tap with piercing connector inside of breaker but in side of disconnect ? Breaker is being feed with parallel wires to each leg of breaker .
 
engelectric said:
Here what exist , transformer 150 kva parallel feeder to two 800 amp 3 phase breaker each 800 amp has 6
Meter total plug in . The power company doing testing to see what other added load Can be added. If I understand you can add to breaker but only if there are twin port on top of breaker to land the wires, but can u tap with piercing connector inside of breaker but in side of disconnect ? Breaker is being feed with parallel wires to each leg of breaker .
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My understanding is that you have two 800 amp service disconnecting means. You can have up to six, so you can add additional disconnecting means. Whether or not you can supply from the existing conductors will depend on load calculations and size of existing conductors. If the existing load plus new load is less than ampacity of existing conductors then you can supply this from existing.

If it is determined that it can be done then you still have the issue of how to do it. You mentioned twin ports on the breaker, but also mentioned parallel conductors, so your ports may all be used. If so you may need to add some other method of termination and possibly even do so in a separate enclosure.
 
Sorry for the confusion , 200 amp 3 phase meter. on line side of meter I want to tap off a 800 amp 3 phase disconnect,inside of 800 amp encloser to feed the meter.The tap will be on line side of 800 amp disconnect that go to the 150 kva transformer.These feeder are paralle, weather I land the tap off breaker port or pierce with connector in side of 800 amp enclosuer, is this excepted by the code.
 
engelectric said:
Sorry for the confusion , 200 amp 3 phase meter. on line side of meter I want to tap off a 800 amp 3 phase disconnect,inside of 800 amp encloser to feed the meter.The tap will be on line side of 800 amp disconnect that go to the 150 kva transformer.These feeder are paralle, weather I land the tap off breaker port or pierce with connector in side of 800 amp enclosuer, is this excepted by the code.
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I believe you mean acceptacle... but the answer is still conditional on more than just whether a tap is permitted, either way.

1a) To install tap conductors into lugs on the line side of the 800A breaker, you either have to have an available empty hole, or a hole already occupied by one conductor must be rated for two conductors (very rare in the size conductors you are working with). A typical arrangement might be, if breaker currently has two-hole lugs, to replace with listed-for-the-breaker three-hole lugs appropriate for all conductors to be connected.

1b) You can used conductor-piercing tap connectors as an alternative if there is enough room in the breaker enclosure. In this case, you have to tee tap each individual service conductor. That is, you cannot just tap one of the two sets... you have to tap both sets.

2) The existing service conductors (and upstream equipment, if any) must be adequately sized for the existing and added load.
 
ggunn said:
Too bad. I liked acceptacle. :D
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Glad you like it.:cool:

Perhaps a new combination word form replacing 'acceptable receptacle'. :huh:

But really, fingers must have taken over... remnant of having typed 'receptacle' much more often, in combination with posting in the wee hours of the morning.
 
Smart $ said:
Glad you like it.:cool:

Perhaps a new combination word form replacing 'acceptable receptacle'. :huh:

But really, fingers must have taken over... remnant of having typed 'receptacle' much more often, in combination with posting in the wee hours of the morning.
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In a somewhat related story...

Back in the dark ages when "A small step for (a) man..." was only a few days away, a NASA engineer was being interviewed on the Today Show, where he was describing in detail how the moon landing and the subsequent return to Earth was to be accomplished. This fellow was the stereotypical engineer type, complete with white shirt, pocket protector, black rimmed glasses, and no personality whatsoever. When he got to the part about the launch from the moon to reconnect with the command module, he talked at length about "the ascend engine", but with his thick Southern accent it came out as "the ass end engine", which was strangely appropriate, since that engine was on the... well, that end of the spacecraft. He said it over and over again, and every time he did, the interviewer struggled mightily to keep a straight face with varying degrees of success. The engineer was oblivious, of course.
 
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ggunn said:
In a somewhat related story...

Back in the dark ages when "A small step for (a) man..." was only a few days away, a NASA engineer was being interviewed on the Today Show, where he was describing in detail how the moon landing and the subsequent return to Earth was to be accomplished. This fellow was the stereotypical engineer type, complete with white shirt, pocket protector, black rimmed glasses, and no personality whatsoever. When he got to the part about the launch from the moon to reconnect with the command module, he talked at length about "the ascend engine", but with his thick Southern accent it came out as "the ass end engine", which was strangely appropriate, since that engine was on the... well, that end of the spacecraft. He said it over and over again, and every time he did, the interviewer struggled mightily to keep a straight face with varying degrees of success. The engineer was oblivious, of course.
Click to expand...


If this were almost any other forum than MH, I would be tempted to tell the story of Ole Johnson and his interview on local Minnesota TV about his experiences as a bomber pilot during WW II.
 
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