I have a problem that, for now, has me stumped.
The building is 3 years old; 5 years before, it was a patch of dirt. There has been extensive utility work done in that area. The building is served by it's own pad-mounted transformer, 208 3 phase.
The building itself has 6 tenant meters, and a 'house' meter. My problem is with circuits served by the house meter; other areas seem to not have the problem I am addressing.
While the other services have 3 phase HVAC loads, the house meter only serves nine single-phase 120 circuits. Five of these are lighting circuits, and one is the lighting controls.
My problem? I an losing electronic HID ballasts. 17 of 39 so far. The ballast maker tells me they look as if they received some sort of voltage spike. Lighting circuits are loaded to about 8 amps each.
I have also lost a photocell - 25 amp rated, controlling about 8 amps of HID pole lights.
Finally, I had a new Intermatic electronic timer, with battery back-up, fail several times to keep time. That is, it would suddenly drop an hour or two. This timer works with a photocell to control the two lighting contactors. These controls have their own neutral to the panel.
All panel connections are tight.
None of the tenant spaces are losing fluorescent ballasts, or experiencing light flicker.
Any thoughts?
