View Full Version : Service Protection
genoaark
Sep 21, 2009, 04:56 PM
In the past, has National Code ever approved an electrical service to pass directly from the transformer to an electrical breaker box with out protection of a disconnect, fuses or breaker? Or would that have always been a bad idea?
stanfortyman
Sep 21, 2009, 04:58 PM
Honestly, I don't get exactly what you are asking.
If there are less than six breaker throws then no main disconnect or breaker is required.
hkstroud
Sep 21, 2009, 07:39 PM
KISS put an interesting post about the history of the NEC in this post
https://www.askmehelpdesk.com/electrical-lighting/fyi-vintages-house-wiring-398059.html
He gave a link to
History of Residential Wiring Systems (http://www.codecheck.com/cc/wiring_history.htm#nmnoground)
In that link it looks like the New York Board Fire Underwriters in 1881, established a requirement for a disconnect at the building entrance.
tkrussell
Sep 22, 2009, 02:56 AM
If you are referring to the utility transformer, no protection is required at the secondary of the transformer serving a service panel. The panel will need a main breaker to protect the service.