On Tue, 6 Sep 2005 17:54:59 -0500, "Greg O"
wrote:



Contactors can and will fail closed! Not a good idea for a transfer switch!
I could not count the number of failed closed contactors I have replaced in
the last six years!!
Greg

I suppose you COULD use a DPDT contactor - but then why not just use
the old standby knife switch. The contactor needs power to activate
it.

And if the contactor sticks in the line position you can't use the
genset. If it sticks in the genset position, you cannot connect to the
grid. - so you are back to manually operating it anyway. Back to the
knife switch.