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How to Replace 3 Lamp Instant Start Ballasts
Replacing a ballast of the same type (3 lamp with 3 lamp, instant start with same) is fairly simple. The wiring connections and colors match up.
3 Lamp Instant Start Ballast Replacement Diagram
3 Lamp Instant Start Ballast Replaced with 4 Lamp Instant Start Diagram
Replace 3 Lamp Instant Start Ballast with 4 Lamp Instant Start
In this example, a fixture with a 3 lamp instant start ballast is replaced with a 4 lamp instant start ballast. The colors of the old and new ballasts do not match, making this a little confusing. The two yellow wires on a 4 lamp instant start ballast are connected together inside the ballast. Find 4 Lamp Instant Start Ballasts
- Cut and cap one yellow and one red or blue wire with a wire nut.
- Connect each of the blue ballast wires to each of the two blue lampholder wires.
- Connect the red ballast wire to the third blue lampholder wire.
- Connect the yellow ballast wire to the red lampholder wire.
3 Lamp Instant Start Ballast Diagram
Factory wiring