400 Amp Services Engineered???????

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mwm1752

mwm1752

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Aspen, Colo
A jurisdiction near mine has started to require an Electrical Engineer to design services over 400 Amps prior to permit approval. NEC 215.5 is the closest article I've found to support this but it refers to feeders not service laterals. I disagree with the notion that Electrical Contractors cannot design the services over 400 Amps properly. The inspector should be reviewing the work for compliance whether an EE or an EC designs the service. I am not sure there is an ordinace supporting the requirement. Does anyone know of a same requirement elsewhere or have more code to support it.
 
A lot of jurisdictions around here require it. I'm not sure if they allow an EC to do it or not. They also require plans, they figure that if you need 400 amps, then it's probably big enough to take a look at.
 
Are the requirements per NEC or the juristdictions ammendment? IMO an EC should be able to design all services, they still should be reviewed.
 
mwm1752 said:
A jurisdiction near mine has started to require an Electrical Engineer to design services over 400 Amps prior to permit approval. NEC 215.5 is the closest article I've found to support this but it refers to feeders not service laterals. I disagree with the notion that Electrical Contractors cannot design the services over 400 Amps properly. The inspector should be reviewing the work for compliance whether an EE or an EC designs the service. I am not sure there is an ordinace supporting the requirement. Does anyone know of a same requirement elsewhere or have more code to support it.
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...if the local JHA requires it, the NEC has no say.
 
I Designed ...

I Designed ...

I designed a 3-phase 120/208 800A service entrance.
I worked out all the conduit fill and derating.
I put in a "tapped before main" panel for emergency lighting, fire alarm circuit, and voltage test points.
I put in a breaker in a box feeding the surge protector.
Demonstrated meeting the 6 handle rule
Did cross sections of the feeder wiring trough to demonstrate meeting the maximum conductor count at all points.

Brought all this paperwork and filled out the electrical building permit.
When I handed it to inspector he looked at me like I had three heads.

Guess they were not use to journeyman electricians being so detail oriented.
 
I have seen installations of a large single load of 400 amps or more that are less complex design wise than some 100 amp supplied installations. I believe this is a dumb rule to say it takes more education to design just because it is 400 amps or more.

Same installation with primarily dual voltage motors installed at 240 volts instead of 480 volts would change the requirements if the 240 volt install was 400 amps. Yet the 480 volt install probably has a little more complexity because there may be 120 volt transformers to install, otherwise biggest difference is physical size of gear and conductors.
 
Closest I've come is when a local factory wanted to but on an addition and do there own wiring. They hired us to do a one line diagram to satisfy city requirements. We had put the 1200 amp service in a few years earlier. Didn't require an engineer for either. I have wished some jobs were engineered, instead of just designed.
 
ptonsparky said:
I have wished some jobs were engineered, instead of just designed.
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Two principal residences back the designer for our major remodel looked at the corner of the upstairs bathroom where five different angled ceiling planes came together, drew a detail circle around the corner on the framing sheet and wrote: "To be determined by carpenter."
 
GoldDigger said:
Two principal residences back the designer for our major remodel looked at the corner of the upstairs bathroom where five different angled ceiling planes came together, drew a detail circle around the corner on the framing sheet and wrote: "To be determined by carpenter."
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I think there are instances where that sort of thing is appropriate, since the person doing the actual installation probably knows quite a bit more than I do about the particulars of how things come together in the field. I wouldn't dream of telling an EC exactly how to secure a device box or route a conduit, for example (unless there was an Owner spec or some other very compelling reason to do so). Your example of the framing does seem a little extreme, though -- less like means and methods, and more like laziness on the part of a designer who didn't want to take the time to figure out how it should be done.

As for the OP, my experience has been that you can argue and complain all you want, but if the Plan Checker/Inspector has a line in his little book that says an EE has to design services over 400A, he's not likely to back down.
 
The PE requirement would kick in under state law. Each state will be different. In Connecticut, I usually cite CGS 29-276c. The requirement varies by use group and sq ft size. Apartments over 20 units, short stay rental rooms, high hazard may be PE stamp over 20,000 sf. Business, Industrial over 150,000 sf. Don't quote me, I'm guessing from memory, but you can look it up.

I have also heard PE required over 5000 sf but I don't have a good reference for that. 29 are the public safety statutes. There may be something else in the licensing statutes.

I'm sure the statute does not say "over 400 amp". You may want to ask for the code reference and look it up.
 
None of our personal feelings or experiences have a thing to do with it.

If the AHJ requires an engineer you will need to get an engineer.
 
__dan said:
The PE requirement would kick in under state law. Each state will be different. In Connecticut, I usually cite CGS 29-276c. The requirement varies by use group and sq ft size. Apartments over 20 units, short stay rental rooms, high hazard may be PE stamp over 20,000 sf. Business, Industrial over 150,000 sf. Don't quote me, I'm guessing from memory, but you can look it up.

I have also heard PE required over 5000 sf but I don't have a good reference for that. 29 are the public safety statutes. There may be something else in the licensing statutes.

I'm sure the statute does not say "over 400 amp". You may want to ask for the code reference and look it up.
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150,000 sf is small, just under 3.5 acres. What about irrigation machines that water 160 acres?:p

I have also seen livestock buildings that are maybe 200K - 300K sf, that have nothing special in them except for minimal lighting and tank heaters for watering units.
 
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Should there be an official public admendment listed for this juristdiction or do you follow "cause I say so" rule without specific code. I will look at state statues good Idea. Here your shall have a master lic in order to contract. For the last 30 years I know about EC's have been installing services here up to 3000 Amps. Alot of the larger projects have EE's but where is the code requirement. Some are more complicated than others but both EC & EE are equally capable.
 
NEC mentions "qualified" individuals in different places but does not set the rules of who is actually "qualified" to do anything. Who is qualified and what may be required is up to the AHJ.
 
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