Electrical 101

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Instant start ballasts use a single wire for connections to each end of a fluorescent tube. A shunted lampholder connects the lamp pins together. Generally instant start ballasts are wired in parallel.

Find Instant Start Ballasts

2 and 3 Lamp Instant Start Ballast Wiring

2 and 3 lamp instant start ballasts use blue wires for individual connections, and red wires for common connections. Black wire is for line voltage and white wire for neutral. An instant start ballast uses a single wire which connects from the ballast to each of the lamp terminals.

Instant Start Ballast Wiring Diagrams

Instant Start Ballast Wiring

2 Lamp Instant Start Ballast Wiring Diagram

2 Individual wires, 1 common wire

3 Lamp Instant Start Ballast Wiring Diagram (2 Ballasts)

3 Lamp Parallel Ballast Wiring Diagram (2 Ballasts)

One 2 lamp and one 1 lamp ballast

4 Lamp Instant Start Ballast Wiring Diagram

4 Lamp Parallel Ballast Wiring Diagram

4 Individual wires, 2 common wires

4 lamp instant start ballasts and 2 lamp rapid start ballasts use blue and red wires for individual connections, and yellow wires for common connections.

An instant start ballast uses a single wire connecting the ballast to each of the lamp terminals.
A rapid start ballast uses two wires connecting the ballast to each of the lamp terminals.

3 Lamp Instant Start Ballast Wiring Diagram

3 Individual wires, 1 common wire

Fluorescent Ballasts

Ballast Wiring

Instant Start Wiring

Rapid Start Wiring 1 to 3 Lamps

Rapid Start Wiring 4 Lamps

Dimming Ballast Wiring

CFL Ballast Wiring

Emergency Ballasts

Tombstone Lampholders

Fluorescent Tombstone Wiring

Instant Start Tombstone Wiring

Rapid Start Tombstone Wiring 2 and 4 Lamps

Rapid Start Tombstone Wiring 3 Lamps

Swap Terminals on Non-Shunted Tombstones