We replace an old xray by new one, the old xray is fed out of 80A breaker in 400A MLO panel - 480V/3PH. We changed the 80A CB by new 125A CB plus feeder size per vendor drawings. We have only 15 days to finish design per owner's request. Which is the best way to satisfy plan reviewer if he asks for load calculation? We don't have much load information for existing 400A panel or existing as-built document. I know metering is another way to do but code requires 30 days of metering or something like that rite?
How to pass inspection
- Thread starter anbm
- Start date
- Status
- Location
- Windsor, CO NEC: 2017
- Occupation
- Service Manager
See 220.87.
any exceptions for 220.87? to meet 30 days metering can make the owner unhappy...:roll:
hmspe
Senior Member
- Location
- Temple, TX
- Occupation
- PE
Do you have manuals for both that show the stand-by load and the impulse load? Impulse load is very short duration and on the systems I have designed is not a part of the load calculation. If the stand-by loads are about the same you may be able to document the existing and new stand-by loads and just say "no significant load change".
- Location
- Windsor, CO NEC: 2017
- Occupation
- Service Manager
Under 220.87 there is an exception...?
- Status