Dimming control of 55W halogen bulb (newbie help please)

[margun]

Hi there,

I'm new here - hope there is someone who could help. I am an optics technician working in the aerospace industry.

I need to control a 55W halogen lamp from off to full output (rheostat/pot?) running off a 12V battery. I'm afraid I am not apt at electronics Is there a solution which would conserve battery life ( with minimal heat wastage) whilst providing the dimming?

Any advice on components, formulae or a circuit would be greatly appreciated.

Regards,

margun

[electrik-gaschief]

sounds like you need a pwm controller. These operate by switching a transistor on and off at a variable ratio( at a speed where you perceive the average amount of power), at min the transistor is off all the time at half power its on then off for the same amount of time at full power its on continuously. The upside of this mode of control is that as the transistor is either off, with no current flow or fully on with little voltage across it hence there is minimal power loss. Do a google search for 'pwm lighting controller' and you will find many diy or ready made solutions. Remember your controller needs to be able to handle; 55/12 or 4.6amps.