Controlling 12V battery output to heating element

[MJC417]

I wired a diesel glow plug to a 12V battery for a tool I'm building. Its very simple but I would like to control the output of the battery so the plug doesn't heat up as much. It doesn't have to be a fine control, anything crude will do. Is this possible without destroying the battery? Glow plugs are tough, no problem there. Any ideas for a simple controller? Thanks, Mike

 

[WHONOES]

How much current does it draw?

 

[Tha fios agaibh]

You could probably use an off the shelf DC motor speed controller, or build your own circuit using a NE555 timer to drive a mosfet by pwm.

 

[MJC417]

Glow plugs draw about 10 amps (AC Delco 60G). Sure, I'll give a motor speed a controller a try.

 

[WHONOES]

If you want to try and build your own controller, you could try the attached circuit for a very simple 555 pwm controller. A version of it has appeared elsewhere on this forum. The transistor will need to be mounted to a small heat sink.

 

[MJC417]

Excellent, thank you. I may have an old 12v fan I can pull a pwm out of.

 

[WHONOES]

Give it a try.