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Mid point ground return wires
This was going to be a more persuasive note, but I forgot and left my copy of
the 1996 National Electric Code book at the shop. But anyway the new rules
specificly state GTO as the correct wire for the returns on a mid point
ground instalation (and specificly say not to attach returns to the building
or it's parts). It also states max. lenght (total) which would be pretty
easy to exceed on a border tube job with a 15000. Ted's note on keeping the
GTO between the trans (secondaries) and the neon short I also think is real
important. I worked on a border tube job (GTO in metal conduit) with 15's
and on each leg whin using a mA meter, the meter would start wild jumping
around stuff when the leads were over about 6 feet long. In talking to some
transformer manufacturers about this they said it had to do with corona in
the conduit and the trans thought it was going direct to ground (hey, I'm
just a mechanical engineer, maybe some of the EE"s on the neon list would
please comment - and not just on my gulibility). From other instals I have
done or seen, if your leads HAVE to be over 6 feet or so, going to a smaller
trans really makes your GTO last much longer in metal conduit. Also using
the best silicone for secondary to neon leads in time will save you money on
service calls. If you're real cheap, use the black GTO fro the end runs back
to the ground on the transformer. Morgan