|
A standard 7ah Gel battery will run my dew heater for a lengthy session, but I only use it on my corrector and use a home made switch mode controller. Using resistors you will need to know what current you are going to draw, then it's simple arithmetic, e.g. a 7ah (amp hour) battery will allow 1 amp draw for (almost) 7 hours 1/2 amp for 14 hours etc. When the current drawn rises to above 1/10 of the AH rating the battery capacity de-rated. The number and value of resistors will depend on what you're trying to heat so as Laurie said there are lots of variables.
|