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#148636 - 07/29/01 02:30 PM HID Ballasts Schematics: CWA
Scott35 Offline

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Registered: 10/19/00
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Schematic of Constant Wattage Autotransformer type Ballast, used to drive one Mercury Vapor [MV], - ANSI type H## lamp, or one Metal Halide [MH] - ANSI type M## lamp.

Similar to Fig. 3.1. above, this Ballast is used to drive one High Pressure Sodium [HPS] - ANSI type S## lamp, or one "Pulse Start" Metal Halide [MH] - ANSI type M## lamp.

This CWA Ballast is used to drive two 400 watt Mercury Vapor [H-33] lamps, or two 400 watt Metal Halide [M-59] lamps in parallel.
Configuration = "Independent Lamp Operation"

Note that these Ballasts use the "Quadri-Volt" type Autotransformer, so input voltage can be either 120, 208, 240 or 277 volts.
The common conductor is common throughout the input [primary] and the lamp screwshell contact, due to the Autotransformer configuration. Use of grounded system conductor for the common is advised - in order to reduce the L-G shock hazard from the lamp's screwshell[s].
If an Ungrounded system conductor is used with the common, the L-G potential will exist on the lamp's screwshell.

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 CWA Ballasts

Scott SET posted 07/29/2001 14:26:00 PDT
Scott " 35 " Thompson
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