electric power availability question

[ridiculously_necessary]

With the truck in my sig, I power nothing more than stock with the current electrical system. I dont know what the alternator puts out, or if it even says. What I want to do is add a 12v 250-400 watt pad heater to my veg filter and would like to know if I can do this or if I would need a high output alternator. I wouldn't flip the heater switch until after I have started the vehicle so the glows and all would be off. or shoudl i be looking at amps?

Also, what do I wire the heater to, a battery or the alternator? Is it ok to hook it to one battery only?

Thanks!

[ono_55]

You should have no problem running your vegy heater. you can power it off the passanger battery. Iam powering 6 kc lights that way just use a relay and a fuse for protection.

[ridiculously_necessary]

fuse, good idea. ok, so any idea how much available power i have before i need an alt upgrade?

[ono_55]

I think our alt puts out 180 amps,my 6kc light draw 150 watts each,have not had any problems running them.Have had them on the truck for two years now.

[ridiculously_necessary]

wow, thats larger than i thought. any idea what the truck uses stock?