1989 Code For Feeder To Detached Building?

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Ravenvalor

Ravenvalor

Senior Member
Location
Triad region of NC
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Electrician
Hello,

Does anyone know whether or not the 1989 NEC allowed for a feeder to be run to a residential storage building with just the two hots and the neutral as long as ground rods are driven?

Thank you,
 
It was permissible in the '89 Code. I don't have a copy handy but I assume the requirement for no other metallic path was in place.
I think the mandatory equipment ground was introduced in '05.
 
I agree with Gus

I will only add that all separate buildings and structures supplied by a feeder require a grounding electrode of some type.

This has been required for a long time with or without an EGC run with the feeder.
 
iwire said:
I agree with Gus

I will only add that all separate buildings and structures supplied by a feeder require a grounding electrode of some type.

This has been required for a long time with or without an EGC run with the feeder.
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If memory serves me well, I may go out on a limb saying that we had a few years here in NC where ground rods or any type of grounding electrode were not required. This was the case at least for residential wooden storage buildings.

Thanks to all for the great advice.....
 
Ravenvalor said:
If memory serves me well, I may go out on a limb saying that we had a few years here in NC where ground rods or any type of grounding electrode were not required. This was the case at least for residential wooden storage buildings.
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For one branch circuit (this includes a multiwire branch circuit) no ground rod is required. As soon as you go to a feeder the NEC requires the electrodes. Of course local areas make changes. :)
 
Along with the ground rods; you must bond the neutral and ground together (bond Jumper)at the storage building just like a utility service to provide a return path back to the source.
 
iwire said:
For one branch circuit (this includes a multiwire branch circuit) no ground rod is required. As soon as you go to a feeder the NEC requires the electrodes. Of course local areas make changes. :)
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I never understood the reasoning.
 
If you run a 50 amp feeder to a post/pedestal and supply a breaker and it supplies a 50 amp receptacle on same post - you have a feeder to the post and needs a GES. You may be able to call this breaker on the post supplemental if it is same rating as the source end but if it is less then the source end it meets feeder definition.

Now run same conductor to same post but connect directly to the receptacle - it is a branch circuit and no GES is required - can still install one if desired though.


Many people often put ground rods at light poles - though NEC typically wouldn't require them. The light pole is a separate structure but is also usually supplied only by a single branch circuit or by a multiwire branch circuit.



If anyone finds this 1989 NEC I would like to know where you got it, I was using the 1987 NEC in 1989, and moved on to the 1990 NEC in 1990;)
 
kwired said:
If anyone finds this 1989 NEC I would like to know where you got it, I was using the 1987 NEC in 1989, and moved on to the 1990 NEC in 1990;)
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The NEC is published on a three-year cycle, so there was no update between the 1987 edition and the 1990 edition. This excerpt from the history page of the 2014 editon reflects this:

This 53rd edition supersedes all other previous editions, supplements, and printings dated 1897, 1899, 1901, 1903, 1904, 1905, 1907, 1909, 1911, 1913, 1915, 1918, 1920, 1923, 1925, 1926, 1928, 1930, 1931, 1933, 1935, 1937, 1940, 1942, 1943, 1947, 1949, 1951, 1953, 1954, 1955, 1956, 1957, 1958, 1959, 1962, 1965, 1968, 1971, 1975, 1978, 1981, 1984, 1987, 1990, 1993, 1996, 1999, 2002, 2005, 2008, and 2011.
 
retire09 said:
Along with the ground rods; you must bond the neutral and ground together (bond Jumper)at the storage building just like a utility service to provide a return path back to the source.
Click to expand...

That is, if the installation is under the old code and there is no EGC run with the feeder.
 
mbrooke said:
I never understood the reasoning.
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For a single branch circuit, reasoning was there would not be significant amount of electrical equipment to be damaged by lightning. A feeder is treated the same regardless if its 40 amp or 400 amp.
 
iwire said:
For one branch circuit (this includes a multiwire branch circuit) no ground rod is required. As soon as you go to a feeder the NEC requires the electrodes. Of course local areas make changes. :)
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One requirement commonly missed was a separate building required a disconnecting means, and per 225.32 this had to be approved as service equipment (this changed in the 2014 NEC), meaning the disconnect had to have a means to ground the neutral. This could only be done with a panel or fused disconnect, and in that case it became a feeder, the feeder then needed a grounding electrode system.

There was an exception in the 225.32 for residential outbuildings with 3 or 4 way switching, very limited.
 
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