sub panel box wiring


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Old 08-09-17, 09:58 AM
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sub panel box wiring

I have 100 amp panel box that services outdoor items. It is fed by the main house service box. 3 large wires connect to the box, two hot wires to the hot lugs and a neutral wire to the neutral bus. No ground wire. Several 120 VAC breakers and 240VAC breakers are connected. The box is not grounded with a gnding rod.Cannot tell for sure if the gnd bus is separated from the neutral bus. No green screw.Do I need a grounding rod? Anything else?
 
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Old 08-09-17, 10:16 AM
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It doesn't meet current code but may be grandfathered. When was it installed.
Cannot tell for sure if the gnd bus is separated from the neutral bus
It shouldn't be on a three wire service.
The box is not grounded with a gnding rod
If it is on the house it doesn't need one. If it isn't on the house it needs one or two.
 
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Old 08-09-17, 12:23 PM
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The panel should only have a ground rod if it is on a different foundation from the building where the main panel is.

Ground and neutral buses should be bonded for panels with a three-wire feed. It's an old style of powering subpanels but would be grandfathered as long as it was installed properly at the time.
 
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Old 08-09-17, 12:47 PM
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The panel box is mounted on a 4x4 post 100 ft or so away from the house. From your comments it would need a gnd rod or maybe two. Wired to the gnd buss?

Installed sometime between 2005-2007 by previous homeowner. (A guess). Previous homeowner used it to power pool pump and a ground sprinkling system including a water pump in pond 150 yds away. Pond water pump is no longer used.

I purchased property in 2011.
 
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Old 08-09-17, 01:43 PM
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If it is still used for a pool for reasons of safety you need to convert it to 4-wire.
Wired to the gnd buss?
Both the ground buss and neutral buss should be bonded to the box. Often in older 3-wire systems there was only combo neutral ground bar. Not sure what you have. Can you post a picture? http://www.doityourself.com/forum/li...rt-images.html
 
 

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