[TowerTalk] Grounding & Generator Questions

[Doug Rehman]

Below is a diagram of my house. (not to scale...)

|
|  Garage
|         
|___________
	Meters|
		|Door
		|     Office/
Driveway	|      Shack
		|___________________
                     Generators

				Tower

The house has two electrical meters (main residence & in-law apt.) feeding
two separate electrical panels. I run my business from the in-law apt. and
also have the shack there. I'm going to set the house/office up for
emergency power and from pricing generators, I can buy two 15 KW units for
several thousand dollars less than one 25 KW unit.

I've already done the study to know that it will take 25 KW for the
house/office combination. I realize the 25 KW generator is probably a better
unit (liquid cooled versus air cooled, etc.), but the two 15 KW units will
be easier to deal with (lighter to position, come with composite mounting
pads versus building concrete pad, etc.). It also gives me backup to my
backup. Other than hurricanes, we virtually never lose power so the
generators won't get much run time.

I'm planning on mounting the two auto transfer switches above the power
meters (yes, they're NEMA 3- outdoor rated). My problem comes in routing the
power cables from the generators to the switches. I also have an issue with
connecting my shack ground to the power company ground at the meters. I
think I can solve both problems with one conduit, but want to see if anyone
has any thoughts before I proceed.

To get from the generators to the meters, I can either go straight up from
each and through the attic or go up to the fascia and run the conduit around
the outside of the house. I'm leaning strongly towards going around the
outside of the house. (I cannot bury the conduit because of the concrete
driveway.)

Would the metal conduit (probably 2" to accommodate the two lines from the
generators) be satisfactory to use for connecting the shack ground to the
power meter ground? Also, if you see any flaws in my plans, please let me
know.

Tnx,
Doug
K4DDR