Electrics Advice Please

[confusedwhippet]

Hi Guys

Can anyone point me in the right direction? I have a 1974 Series III Landy and the nature of my job means I have a lot of survey work to carry out and I wanted to fit a radio and a ceramic car heater all 12V. I was wondering if I could attach a 3 way cigaretter lighter socket to the inspection lamp fitting and run the radio and heater for a plug that would fit the lighter socket.

Does any of that make sense.

Any advice would be greatly appreciated.

Regards
Stephen

 

[Brim]

Stephen,

The inspection lamp circuit is not very robust for current capacity. It will power your radio okay, but the heater is another matter. Most ceramic heaters utilize a direct resistance element that glows red and creates the heat which is then transferred to the ceramic element. In electrical terms this resistance element is just a little resistance away from a dead short...thus they draw enormous current. Depending upon the rating of the heater some draw 10-15 amps with the fan and element on. So the wiring in the LR inspections lamp circuit cannot handle that amount of current. I'd run the heater from a separate fused line from the battery, or some guys install a cigarette lighter socket on a separate circuit and then power their outboard heaters from the socket.
Cheers,
Steve