Gunner writes:


1. Is it "kosher" to simply hook them to an unused 240 single phase
breaker?

If the lamps fire on 240, I can't see any problem just using
240V. If they don't ignite, then boost may be necessary.
GE seems to say their magnetic 277V ones are rated
"Line Voltage Regulation (+/-) 5 %"
but not sure what that means... less light output at lower
voltage? Won't work at all?

Test a unit for 24H and see what temp the ballast is...

[There are no 240V one listed but the newest electronic ones are
often "120-277"...]

2. Is it better to use a transformer and isolate them from the "mains
power"?

While the 277V ballasts were manufactured to run from a 480
wye to neutral; I can not believe that they have one leg of the
input grounded. But measure with an ohmmeter, and be sure. And do a
bench test with a unit safely fused.


4. How many watts does each 4' pair actually draw? 90 watts? Each of
the 8' fixtures has 2 ballasts, one for each 4' pair.

Measure. Best way would be a test setup with a 120V - 240/277
transformer, and then put a Kill-A-Watt
http://www.p3international.com/products/special/p4400/p4400-ce.html
in the 120 supply. This will tell you the true watts of a
fixture, and the current & power factor. {Watts * time is what
you pay PGE for; but the transformers are limited by current....

Id like to find some pull chain lighting switches that I can mount on
each 8" fixture to either kill the entire fixture..or just half of it

Read what DoN said about relays. Control the fixtures with relays
to gain the flexibility you want. Note the tradeoffs in lamp
life with cycling.
https://en.wikipedia.org/wiki/Electrical_ballast#Fluorescent_lamp_ballasts