Battery Cut Off Switch
Gallery
Fitting and wiring guide for the Lucas-type SSB103 Rotary Battery Isolator Switch
Also applicable to part 463
Classic car battery master cut-off isolator and ignition kill switch. Lucas SSB103 type with round knob - as used on Austin Healeys, Aston Martin, Land Rover, MGA, Morris etc.
Also listed as 76604, 76605, 1B2804, ST330
Panel / dashboard mounted
Connect to the NEGATIVE side of the battery.
Requires a hole 43mm in diameter if surface mounted, or 20mm for rear mounting - remove the knob by removing the small circlip from the shaft end at the rear.
M8 Studs
Suitable for 6v, 12v or 24 volt.
The continuous load rating at 12v is 150amps
Short Max load at 12v (example starting) is 500amps
| Voltage | 12v | 24v |
| Continuous Load | 150 amps | 75 amps |
| Short Max Load | 500 amps | 250 amp |
Rear of SSB103 Battery Isolator Switch
B - Battery Negative terminal
E - Earth - Vehicle body
CB - Contact Breaker connection (Optional) Low Current only.
Some vehicles have a wire (White/Black) from the coil to CB. This serves as an ignition kill-switch (connecting CB to E) when the switch is in the OFF position.
