Originally Posted By: Bob Badger This post was automatically imported from our archived forum.
Hi Jeff I would say Robert is correct and that they are using parallel conductors, in this case two conductors per phase, the only reason for doing this for a ‘small’ service is to keep from having to bend larger conductors.
I do not bother until I get above 400 amps but to each their own. 
For example if we build a 3000 amp service we generally run 8 sets of four 500 Kcmils in 8 separate pipes for a total of 32 conductors. You will not find single conductors rated 3000 amps.
Back to your picture it looks like they say 3/0 on them I can not tell if they are aluminum or copper.
If they are copper 3/0 is good for 200 amps x 2 = 400 amp service.
If they are Aluminum 3/0 is good 155 amps x 2 = 300 amp service. (you might be able to push this out to 350 amps by 'working' the code)
However they put them all in the same raceway which means that the wires need to be derated by 80%.
I will skip all the code references and technicality's but once I do the derating I come out with:
Copper 360 amps which could still be a 400 amp service or might have to be a 350 amp service, it all depends on the calculated load.
Aluminum 280 amps resulting in a 300 amp or 250 amp service.
Now WHY ARE THEY ALL WHITE
In this area this would not get connected but some power companys have odd rules.
Originally Posted By: jpeck This post was automatically imported from our archived forum.
Whereabouts on that roof is that service mast located and how high is it? Certainly does not look like it has the minimum required clearances for that flat or low slope (less than 4/12 for electrical purposes) roof.
That'd be way overkill (nothing inherently wrong with that) for just 4 a/c systems. I inspect many homes with 4,5,6 (and more) a/c systems and they do not have a services like that. Why are all those service entrance conductors white?
How large is the home?
Exposed duct work? I guess you guys don't have a high wind problem, just a shaky earth problem.
Duct does not look properly supported (okay, supported, but not held down) either.
How high are the plumbing vent stack terminals?
What is that parapet wall made of? Masonry? Frame?
Sorry, my mind wondered beyond the electrical mast.
Originally Posted By: jpope This post was automatically imported from our archived forum.
The location of the mast is certainly suspect. I don't even know where the service disconnect will be at this point as the plans actually call for underground service.
The home is three levels and a huge garage, all fed by separate A/C units. 8500 sq. ft. of living space.
Duct work is attached to the supports, no additional tie down requirements that I can find.
Didn't check the plumbing stack height.
Parapet is frame.
-- Jeff Pope
JPI Home Inspection Service
"At JPI, we'll help you look better"
(661) 212-0738
Originally Posted By: jtedesco This post was automatically imported from our archived forum.
Bob’s example is typical for services installed in this manner.
I can barely see the 3/0 on one of the conductors. Are they 3/0 and what type? They are now supposed to be sunlight resistant too and with 6 in a 2 inch raceway - got to know the insulation. Aluminum or copper?
Jeff: Are you making an inspection here? Is the service ready to be connected? Sure would like to see all of it?
Originally Posted By: jpope This post was automatically imported from our archived forum.
jtedesco wrote:
Jeff: Are you making an inspection here? Is the service ready to be connected? Sure would like to see all of it?
These are copper.
I'm not doing a compliance inspection, only QC. The service isn't scheduled for connection until early October.
No service panel is in place at this point, however a 200 amp rated equipment panel has been placed in the interior of the home. No breakers at this point, only the panel box.
-- Jeff Pope
JPI Home Inspection Service
"At JPI, we'll help you look better"
(661) 212-0738
Originally Posted By: jpeck This post was automatically imported from our archived forum.
Then that is probably the stub out for the feeders to the roof mounted equipment.
There will be a real problem with them not being in conduit.
Plumbing vent stacks terminals on that roof will need to be at least 7 feet tall.
The parapet wall needs a top cap flashing, looks like the roof covering runs up the parapet wall and on top of it. I see these pulling loose all the time. If the top of the parapet wall is stucco, then it needs a cap flashing for sure.
I see supports under the duct, but no strapping over the ducts. And I don't see supports for each section of duct work.
Originally Posted By: jtedesco This post was automatically imported from our archived forum.
Was an electrical permit issued by the city of West LA, or LA, along with all of the other permits (picture?), and was the service installed by a utility company employee or local contractor?
Originally Posted By: rpalac This post was automatically imported from our archived forum.
After seeing the second picture it is evident that this ois the feeds for roof units and the cables are parallel feeds to meet the ampacity requirements probably or possibly even dule feeds run in the same feeder. Nothing out of the ordinary.
Originally Posted By: Bob Badger This post was automatically imported from our archived forum.
Ryan Jackson wrote:
I'm reviewing plans right now for a $100,000,000 project that has two 4,000 amp, 480 volt services. 
Ten sets of 600 Kcmils for each service?
We did a very large building in PA with seven 3000 amp 480 services, but they might not have really been services they might have been feeders, I was only out there 3 weeks I did not get that deep into it.
Originally Posted By: Bob Badger This post was automatically imported from our archived forum.
rpalac wrote:
After seeing the second picture it is evident that this ois the feeds for roof units and the cables are parallel feeds to meet the ampacity requirements probably or possibly even dule feeds run in the same feeder. Nothing out of the ordinary.
Bob p.
You can not feed the HVAC equipment in this manner and you can not remark the white conductors in conduit.
Originally Posted By: jpeck This post was automatically imported from our archived forum.
Why can’t you re-identify white? Code says they MUST be permanently re-identified by painting or some other approved means, anyone know of any paint approved to be put on electrical conductor insulation?
They can be permanently re-identified, at all accessible locations, not just there. Plus, you can leave them hanging out there like that, they need to be in conduit, so let the electrician do it correctly, and, while they are doing it correctly, replace the feeders to the roof top. OBVIOUSLY, they ARE going to install a disconnect panel up there, RIGHT?
