Originally Posted By: waksell This post was automatically imported from our archived forum.
Hypotheticaly,
If you have a 200A meter, 100A feeders, 150A main breaker and panel, you have a 100A service rating.
(a chain is only as strong as it's weakest link)
It would be possible to pull more amps through the main breaker than the feeders could carry and it would fry the feeders.
It seems that an HI would flag a dangerous situation like this.
Or should you just report service size and leave it at that?
With underground service I can't size the SEC to the meter. Does the utility (or ever who puts in the meter) ever install a meter that is rated higher than the SEC?
Is it possible?
Can't assume, I guess just note limitations?
P.S. Do all meters have a rating on them that begins with CL?
Like CL100, CL150, CL200?
I assume that CL stands for current load? Am I right or wrong?
Originally Posted By: mcyr This post was automatically imported from our archived forum.
Wesley; Whether or not you have a 200 amp meter or not, if the panel is 100amps, the main breaker can not be 150.
If this is the case, you need to write up the fact that the main breaker is over rated for the panel capacity.
Originally Posted By: Greg Fretwell This post was automatically imported from our archived forum.
Gee whiz info
Service Conductors are the wires from the utility to the service point (usually the drip loop). They belong to and are sized by the utility (NESC).
Service ENTRANCE Conductors go from the service point to the meter and then to the service disconnect. They belong to the customer and are sized by the NEC, usually 310.15(B)(6) in a dwelling.
Feeder is the wire after the first disconnect to a subsequent panel if present. It is sized by the NEC and if it is not an extension of the service entrance, feeding the entire house load, it is sized by 310.16 (larger) since they can't assume load diversity that allows 310.15(B)(6).
Branch Circuit is the wires from the final overcurrent device to the load.
In your case are you saying the SE conductors feeding the 150a disconnect are 4ga copper? If so you are right. It is not properly protected. If it is #1cu they are OK
Originally Posted By: Greg Fretwell This post was automatically imported from our archived forum.
Gee Whiz part 2
The one I missed was
Service Lateral, that is an underground service conductors and it may or may not belong to the utility but it will be sized by 310.15(B)(6) since there is no air cooling going on.
Some utilities will "own" this, others may have the customer own it.
Originally Posted By: Greg Fretwell This post was automatically imported from our archived forum.
I am just a code junkie from the school of Tedesco.
I was always chipping around the edges of the electrical trade, building computer rooms but about 15 years ago I got hooked up with Joe and the “secret society” of electricians who formalized my education. Joe got me IAEI certified in all 3 categories and that led to certification in ICBO, SBCCI along with Florida licensing and an inspector job when I retired from IBM.
Originally Posted By: lgoodman This post was automatically imported from our archived forum.
Wesley,
My impression is that you do not want to report that the breaker is over-rated for the panel capacity but rather that the rating of the breaker is in excess of the cables ampacity.
If I read correctly both panel and breaker are rated at 150A, right?
Breakers protect wireand wire size is the main determining factor in breaker rating.
Meters and panels can be rated higher than main breaker. After all that just means they can take more load than the breaker can dish out. They are not imposing a load, they are withstanding a load.
Breakers can not be larger than the wires ampacity.
