Schematic of the Constant Wattage Isolation Transformer type Ballast for operation of one Mercury Vapor [MV] - ANSI type H##, or one Metal Halide [MH] - ANSI type M## lamp.

Similar to the Schematic in Fig. 4.1. above, except this one is for operation of two MV or MH lamps in series.

Note the secondary winding - the Reactor coil - is electrically isolated from the primary winding [or the "Line Input"].
The Resistor[s] shunting the Capacitor[s] are just to drain the residual charges from the Capacitors after power is removed - hence the name "Draining Resistors". They perform no other useful function in these circuits other than drain the Caps.

Side Note: They would create an RC bandpass filter in this state, but that's not the intended result - just a simple side effect

Please feel free to ask questions, make comments, or participate in discussions on these Ballasts in the Theory area under the topic heading of:

Discussions on: HID CW 1 and 2 lamp Ballasts

Set 'a spell, take 'ya shoes off... Y'all come back now, 'ya hear???
[This haz beeeen aaa Filmwayys Prezzzent-ayyy-shun]
Beverly Hillbillies just ended and the show has me under it's spell!! I am powerless against the Clampetts!!!.... Must Go To The See-Ment Pond [monotone, robotic voice]. Must Go Shoot Some Bill-eee-ards To Go With The Opossum Pie.
Ok, I'll stop now I broke the spell

Scott SET posted 07/29/2001 11:18:00 PDT
Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!