Hope you are well. I'm currently working overseas, and this particular area is what they call Force Provider systems. There are transformers(They are called SDC's) that provide 4160 on the primary side, and 120/208 on the secondary. On the outside of these transformers are connectors for the force provider cables to hook up to. They are about 8 60 amp 3 phase connections and 2 100 amp. The unit allows for a back up generator to be set in place and be hooked up to the 200 amp imput and a switching means to re-energize. There are two ground rods that exist for the transformer. Can the new back up generator grounding electrode be hooked up to these existing rods, or do they need a separate ground rod?
Grounding electrodes
- Thread starter Lobster
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jumper
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I never was involved with the field connections for those units, but I did the internal wiring on a couple of hundred of them.
I am curious, which type of units are you involved with? Army, Navy, or Marines?
Since the transformer and the genset are not going to be supplying the units at the same time, I cannot think of a reason why the two cannot share one grounding electrode system.
I am curious, which type of units are you involved with? Army, Navy, or Marines?
Since the transformer and the genset are not going to be supplying the units at the same time, I cannot think of a reason why the two cannot share one grounding electrode system.
jeremy.zinkofsky
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- nj
Do they classify as auxiliary grounding electrodes?
jumper
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- 3 Hr 2 Min from Winged Horses
Clarify please.
jeremy.zinkofsky
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250.54
jumper
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Let me rephrase:
You asked: Do they classify as auxiliary grounding electrodes?
What are you calling "they"?
jeremy.zinkofsky
Senior Member
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- nj
Sorry, "they" meant grounding electrodes. However, I misunderstood the post and now understand the issue to be about seperately derived systems. If that is correct, wouldn't 250.30(A)(5) hold the answer?
jumper
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- 3 Hr 2 Min from Winged Horses
There may only be one neutral to ground connection in a wye system, but there must be one. It is recommended to have the grounding electrode at the generator. The common question is whether or not the neutral should be bonded at the generator. (Is the neutral grounded at the generator.) You may do this and it is recommended that it be done when the generator is a large distance, or a large voltage potential from the main. If you ground the neutral at the generator, then you must switch the neutral on the transfer switch to prevent having a neutral to ground loop. So the transfer switch becomes four pole instead of three.
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