Originally Posted By: Steven Brewster This post was automatically imported from our archived forum.
I inspected a Mfg home and have the following questions regarding the electrical service. A disconnect is located at the exterior (which is grounded at this enclosure). A three wire feeder cable runs in conduit to the panel in the home (which is also grounded at a separate location). The panel in the home has both the grounded conductors and grounding electrodes on the same bus and the panel is bonded to the bus. Should this service have been a 4-wire from the disconnect? Should the distribution panel in the home have isolated grounds and neutrals and no separate ground? See pics.
I was told recently by a licensed electrician that older (three wire service neutral and grounds on same bus) distribution panels are "grandfathered" into the code and are not required to have isolated grounding electrodes and grounded conductors. New construction, of course would require.
Originally Posted By: jpope This post was automatically imported from our archived forum.
Steven Brewster wrote:
I was told recently by a licensed electrician that older (three wire service neutral and grounds on same bus) distribution panels are "grandfathered" into the code and are not required to have isolated grounding electrodes and grounded conductors.
I can tell you, this statement is wrong.
What type of conduit was the three wire feed in (metallic or non)? Did the unit have its own GEC?
Older units commonly have this setup. As long as there's no metallic connection between the service and load side panel, and the unit is properly grounded with its own GEC, it may be okay, but I doubt it.
The cable/TV and telephone are most likely grounded at the unit. Several other conditions may bond the service to the unit and make the three wire feed improper.
-- Jeff Pope
JPI Home Inspection Service
"At JPI, we'll help you look better"
(661) 212-0738
Originally Posted By: Steven Brewster This post was automatically imported from our archived forum.
Jeff,
The service to the load side panel is in non-metallic conduit and both the load side panel and the service are grounded respectively at their panels.
There are other issues that will require a lic. electrician to repair but just did not know the particulars about mfg. housing electrical service.
I agree with you on the 4 wire issue. This is the situation I encountered a service equipment/distribution feeds this panel in the garage. I wrote it up that it required 4 wire and he told me it was grandfathered.
Originally Posted By: Steven Brewster This post was automatically imported from our archived forum.
Jeff,
Sorry, the second set of pics I posted were from another inspection and the service equipment-Distribution (I may be calling it wrong) was beneath the meter and the other panel was in the garage. This concerned the statement regarding grandfathered.
I realize that the pic you posted was the disconnect or service equipment.
Thanks for you feedback. I will soon have all the correct terminology stuck in my head.