[timoteo]

I have installed a 208 - 460 step-up transformer for a new machine. The inspector says I need an additional ground wire. Currently have:

Ground wire from panel to transformer chassis.
Also sank an 8' ground rod at transformer.
ground wire from chassis attached to ground rod.
Machine ground wire attaches to chassis.

Inspector wants me to install an additional wire to chassis, and run it all the way back to the main building ground rod (140', through neighbors unit).

Does this sound legitimate? I'm all for safety, but 3 ground sources seems excessive.

Thank you.

 

[Wildie]

I have installed a 208 - 460 step-up transformer for a new machine. The inspector says I need an additional ground wire. Currently have:

Ground wire from panel to transformer chassis.
Also sank an 8' ground rod at transformer.
ground wire from chassis attached to ground rod.
Machine ground wire attaches to chassis.

Inspector wants me to install an additional wire to chassis, and run it all the way back to the main building ground rod (140', through neighbors unit).

Does this sound legitimate? I'm all for safety, but 3 ground sources seems excessive.

Thank you.

The inspector is the boss! You may be able to appeal this to his supervisor. It will likely be easier to run the ground.

 

[frenchelectrican]

Is this set up a single phase or triphase this will make the diffrence on the format of proper grounding.

And some case again I say you may have to ground out one side of conductor to order meet the NEC codes but again first answer the first question then we will guide ya the rest and btw most case 208 volts is typically a commercal voltage { quite few resdentals do use them if they are on the 208Y120 network }

Merci,
Marc

 

[micromind]

I'd politely ask for a code reference. The ground wire you have from the 208 panel to the transformer is essentially the same thing he is asking for, provided the panel is indeed grounded.

 

[timoteo]

It is a commercial building. 208 3 phase incoming. So, what is the additional ground supposed to accomplish?

 

[wareagle]

I have installed a 208 - 460 step-up transformer for a new machine. The inspector says I need an additional ground wire. Currently have:

Ground wire from panel to transformer chassis.
Also sank an 8' ground rod at transformer.
ground wire from chassis attached to ground rod.
Machine ground wire attaches to chassis.

Inspector wants me to install an additional wire to chassis, and run it all the way back to the main building ground rod (140', through neighbors unit).

If the EGC from the panel to the transformer chassis is installed correctly and all of the EGC's are installed, it would be the same thing as the additional ground that the inspector wants. You should have an EGC from the main to the transformer already in place. There is no need for another.