Trying to remember since I had several. If I remember, the primary had three taps and a common. The common went to
neutral, the hot looped up to the
power switch on the light then back down (5 pin
twistlock) and went to the tap
switch which selected one of the three primary taps on the
ballast and allowed you to compensate for
line voltage. The secondary side had the
capacitor in series with the output. One of the two
ballast output wires was also tied to
neutral. Those two wires then looped up to the lamp. So, the 5 pin
twistlock contained, Hot, switched hot,
ground,
ballast out 1/
Neutral, and
ballast out (via cap) 2. In the lamphouse, switched and unswitched went to the
power switch and at least one
safety interlock. Switched then also connected to the fan. The other side of the fan(s) went to the
ballast output that was tied to
neutral. The
ballast output then went to the igniter module, which also looped to the igniter push
button. The output of the igniter module went to the lamp via some silicon high
voltage wires. Now in all fairness, the last time I set my eyes on this was 1986, but I am pretty sure...