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Posted By: schenimann generator install - 07/20/12 02:14 AM
I am pricing a 20ke gen install. The house has a panel back to back with the meter base. When I bring my 4 wire to the panel that currently has 3 wires do I need to separate the grounds an neutrals?
Posted By: gfretwell Re: generator install - 07/20/12 02:45 AM
What kind of transfer equipment are you using? Do you switch the neutral?

The objective is to have one and only one bonding jumper at any time.
Posted By: schenimann Re: generator install - 07/20/12 03:03 AM
The HO purchased a kholer gen and a transfer switch from HD. I don't think the neutral will switch.
Posted By: gfretwell Re: generator install - 07/20/12 04:30 AM
If you do not switch the neutral, your service bonding jumper is the jumper you use so you want to isolate the neutral at the generator. This is not a separately derived system. You still bond the EGC of the generator to the grounding system at the house.
Posted By: schenimann Re: generator install - 07/20/12 04:46 AM
I will install a disconnect before the switch. At that disconnect I will isolate the neutral from there. From the switch to the panel I will have them isolated. However, they are not currently isolated in the panel. I will need to separate them in the panel, correct.
Posted By: gfretwell Re: generator install - 07/20/12 05:19 PM
If you isolate the neutral in the panel, where is the main bonding jumper?
Posted By: wire_twister Re: generator install - 07/21/12 01:33 AM
The Kohler switches I have installed have an isolated neutral buss with enough space for a neutral from the disconect, the load, and the genset, making the main bonding jumper in the meter pan the only one, weather you are on utility or generator power.
Posted By: gfretwell Re: generator install - 07/21/12 03:02 AM
Exactly right Jimmy. The thing is you only have one bonding jumper. It is there in any configuration but only one at a time. If you switch the neutral, the bonding jumper moves with it.

Soares has some great pictures, at least they did have on my ancient copy.

Posted By: shortcircuit Re: generator install - 07/26/12 12:33 PM
If your doing a whole house transfer, Kohler has a Service Entrace rated transfer switch and the neutral bond will be made there. You need to seperate all neutral and grounds at the exisisting main panel because it is now downstream from the main disconnect. (remove the bond screw also)

You will also have to relocate your grounding electrode conductor from the existing panel to the new service entrance rated transfer switch.

shortcircuit
Posted By: schenimann Re: generator install - 07/27/12 10:10 PM
The HO purchased the package from Lowes that comes with the standard transfer switch and not the service entrace switch. Therefore I will need to put in a 200amp disconnect before the switch. The bond will be made in the disconnect and everything else will be seperated downstream.

I worded it wrong in my previous post. When I said separate my grounds and neutral at the disconnect I meant they would be bonded there and go out separate after that to the switch and panel.
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