I bought a heated vest from Gerbings which draws about 77 wats or 7amps of 12V power. It has this low tech thermostat that keeps turning on and off every second or twice a second to regulate the power that goes to the vest and thereby the heat. There is an LED tha blinks on and off that is the indicator. If you turn it up it just blinks faster until it goes full solid (no on/off).
The problem is that when it is going on/off my headlights lose and then gain brightness. Its probably the shock or surge when the circuit is turned on off on and so forth repeatedly.
What kind of circuit could I use to prevent this? I am pluggin into the cigarette lighter called a BMW power outlet.
Do you think this would damage the alternator or battery if I leave it like this?
This is the vest:
This is the temp controller.
Any ideas would be appreciated.