kbsparky
Senior Member
- Location
- Delmarva, USA
Many breakers of that size have adjustable trip ratings. Simply adjust it to slightly less than 2000 to equal your 1995 Amp feeder capacity. 
310.4 nec
- Thread starter contactm
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jumper
Senior Member
- Location
- 3 Hr 2 Min from Winged Horses
Many breakers of that size have adjustable trip ratings. Simply adjust it to slightly less than 2000 to equal your 1995 Amp feeder capacity.
I thought that 240.6(B) said that it would still be considered a 2000 amp rating unless you can meet the requirements of 240.6(C).
- Location
- Illinois
- Occupation
- retired electrician
Given the shortness of this run, I would expect that more than 10% of the run is not underground and you would be required to use the ampacity of the above ground portion of the run.
- Location
- Illinois
- Occupation
- retired electrician
It doesn't work that way. The equipment also has to be listed for use with at 90?C. It is easy to find conductor termintions listed for 90?c, but not so easy to find equipment so listed.
- Location
- Windsor, CO NEC: 2017
- Occupation
- Service Manager
Well, a junction box could be cut in below the disconnect, as big a PITA as that would be.
Five amps can be a heckuva headache!
Five amps can be a heckuva headache!
- Location
- Wisconsin
- Occupation
- PE (Retired) - Power Systems
With todays 'electronic trip' breakers 240.6(C) is so easy to meet, it is a wonder it is even still in the code. All it takes is provisions for a wire tie to seal the adjustment access cover in order to provide a feel good sense of security. Past CMP comments indicate it believes that changing breaker settings is similar to replacing fuses which are less than the switch rating (i.e. 300A fuses in a 400A switch).
Cow
Senior Member
- Location
- Eastern Oregon
- Occupation
- Electrician
Would it be possible to have an engineer sign off on it?
kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
Cow
Senior Member
- Location
- Eastern Oregon
- Occupation
- Electrician
I'm simply throwing out ideas here....
- Location
- Wisconsin
- Occupation
- PE (Retired) - Power Systems
kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
I would think it only happens in rare cases. Even then, the engineer is basically taking on liability by putting his approval on something that otherwise does not meet codes or other standards, so he is not likely to want to do such a thing except in very rare cases, and if that does happen, then watch out for what his seal of approval may end up costing.
- Location
- Wisconsin
- Occupation
- PE (Retired) - Power Systems
I know of no State licensing authority that would consider it proper practice for an engineer to ignore, if not blatantly go against, a national code.
It seems contractors like to think that engineering approval overrides applicable codes but doesn't. Only the AHJ can deem installations to be in compliance.
kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
That is probably correct. Sections like 310.15(C) maybe are misunderstood to mean an engineer can do whatever they want, when in fact there is still a guideline for the engineer to follow.
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
So where is the OP-- starts a thread and doesn't return .... :?
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