when up grading an exsisting service to a new service , i am trying to find what code says just how much past the service are you required to change over to new wiring vs leaving the existing wire alone. replaced new service drop , meter base , panel and used exsiting wire . the house has a sub panel , (fuse box) and inspector wants me to size wires from fuse box with new s fuses for the exsisting circuits to house. these circuits are all fused with 30amps and all circuits in fuse box are all single poles. the wires look to be 12 ga. and if i fuse with 20amp wondering if fuses might start blowing because of how much these old circuits have on them. owner says he has never had a problem before and house is over 70 yrs. old. thanks for any input..
... If I read the Code book right...,a #12 awg.wire is to be protected at NO MORE than 20 amps...if this constitutes a problem,then it's time to divide the circuits up,if you can find splice points,..or junction boxes in the basement,or attic,...etc.Or else,run new circuits from the new panel.I would advise the H.O. that although a new service is beneficial,it's not an end-all cure.This work is going to be inspected,and as you already stated,the inspector wants you to assign the correct size OCPD for that circuit,based on it's conductor ampacity.If the inspector sees a 30 amp breaker in the panel,on a #12 wire,he's gonna fail you. Good Luck,...Russ
.."if it ain't fixed,don't break it...call a Licensed Electrician"
Re: old work#40049 07/11/0408:43 AM07/11/0408:43 AM
S-type tamperproof fuses, correctly sized for the wire guage, address the hazards introduced by overheating conductors and connections, however, its a fair bet that the history of heating at your job, along the conductors where the current of individual loads sums to its highest total, has toasted insulation, perhaps disasterously.
Re: old work#40050 07/11/0408:48 AM07/11/0408:48 AM
Does the state legislature adopt it?, or is it a county or municipality? The way I understand it is, the UCC, or even the NEC, for that matter, doesn't dictate anything until some entity is given the legal power to enforce the code. If it is the State, the "law" ends at the border, same for the county or city or etc.
In Minnesota, the State adopts the NEC for the whole state. Yet, the State Legislature says very little about when and how upgrading of wiring in existing occupancies is to occur. In Minnesota, that is left up to smaller agencies such as the County, City, Municipality or Township.
Interstingly, a seperate set of requirements comes from mortgage underwriters and insurance companies in the form of offering to do buisiness if the dwelling meets their own requirements. These, of course, are not required "by law", and can be ignored if another mortgage or insurance policy can be procured somewhere else without the requirements.
Re: old work#40053 07/11/0410:26 AM07/11/0410:26 AM
Where I am you would have no obligation with this at all. You did a service upgrade. End of story. The inspector can tell you whatever he wants done elsewhere in the house but you don't have any obligation to do it. It is up to him to notify the property owner in writing if he has a problem with something. At this point the homeowner can have the problems repaired. I have had inspectors come through a basement on a service upgrade barking out commands like he's General Patton, "Unplug that cord, staple that bx, put a cover on that receptacle," etc. I usually just nod and say I'll pass the info on tho the homeowner. With all that said this does sound like a hazard that should be addressed by someone.
Re: old work#40054 07/11/0410:59 AM07/11/0410:59 AM
Those 30 Amp fuses, almost certainly, were not put there by accident. There was load that was blowing the correctly sized fuse.
In my opinion, one has to assume that the loads that caused the 30 Amp fuses to be installed, ran for some part of the 70 years that the house has been there. There may not be the same load connected now, but, IMO, one has to assume an overload ran for some amount of time.
Until proven otherwise, the existing overfused branch circuits are highly suspect as potential ignition sources.
Re: old work#40055 07/11/0412:01 PM07/11/0412:01 PM
thanks for everyones input....i agree with the #12 circuits on 20 amp breakers. and i feel like the service should have been all i was resonsible for like u said electricman scott. the problem i am encountering is this is insurance work and as everyone knows they only want to pay as little as possible and when i quoted the job it was only to replace the service but there may be extra work if required. the inspector wanted me to run new circuits to fuse box and splice them there but i told him i would rather not for cost purposes the home owner might have to pay the extra cost and he did not want to pay. dont mind sizing the fuses accordingly just hope i am not getting in to a can of worms and i would have rather did an entire upgrade. and this inspector is trying to bully me around which im not sure how to handle this...
Re: old work#40056 07/11/0412:05 PM07/11/0412:05 PM
Maybe. . .ask him, or his department or office for the codes and ordinances that are in effect by force of law in the area, then ask for access to copies. Or where to get copies. Hopefully there will be web access to the most local requirements.