Quote Originally Posted by LIFRANK View Post
First you have to check the resistance of the heating element in the seat. Then using ohms law you
can calculate the Current(I) drawn if the seat is powered by 12Volts. Once you know the current then
you can go on to calculate the power, for example if the resistance(R) of the seat is 100 ohms and is powered
by a 12 volts battery then the current would be Current I = (V/R ) = 12/100 = 0.12 Amps or 120 milli Amps.
the power drawn would be Power P = (Current^Current*Resistance) = 0.12*0.12*100 = 1.44 Watts. Now lets look at
how this would affect your battery on your boat, if you have a 120 Ampere an Hour (AH) using the example above
it would take (120/0.12 )= 1000 hours to drain your battery, If you fish 8 hours per day your battery would last for (1000/8) = 125 days providing that the seat is the only device connected to the battery. NOTE:This example is only based
on a seat heating element resistance of 100 ohms @12VDC, If the resistance is less the current drawn will increase along with the power drawn and that would definitely affect your battery drain time.You must check the resistance of the heating element then do the calculation.

Lifrank.
Very good, I like that. Thank you. For any decent heat generation 100 ohms resistance won't cut it.