"Nate Nagel" wrote in message
...
Hi all,

I have a Siemens breaker panel in my house that uses QP type breakers.
I purchased a double breaker/TVSS unit to replace two 20A breakers in
the panel. I figure that it is cheap insurance, even though I have no
indications that there's issues with the power locally.

What I would like to know is this. I have a 100A breaker in this box
feeding a garage/outbuilding at the back of the lot. This building
obviously has a subpanel in it for the lighting, bathroom, water heater,
etc. - would it be a worthwhile investment to buy another TVSS for that
panel, or is one at the main panel generally sufficient for all
forseeable issues? IF it makes any difference, this wiring is buried
and all utilities (except phone, which is disconnected) are buried as
well.


I think the one at the main panel is sufficient. I would put any additional
expense and time into making sure that you have a good grounding electrode
system (Ground rods, water pipe grounding, interior metal piping bonded,
etc.).