Ive got my truck parked in the barn and have to run about 75 feet of power cord to it. my question is with that much cord is their any chance of my truck not getting enough current for the heater to work like it should?

 

The length of the cord will affect how many amps the heater draws not the voltage. The only problem you might have is the breaker for the outlet you are plugged into can break if the amperage gets too high. Should be fine though.

 

Only thing I would add is that you'll want a heavy duty outdoor extension cord.

I've seen smaller gauge cords melt when attached to these block heaters.

 

Uhm, no. The longer the run, the more the voltage drop. And the lower the voltage at the resistor (heater), the less current is used there as heat (the rest is wasted as heat in the cord). Get the biggest gauge cord you can find, like Lisa said. The bigger the cord the better for long runs. 12 gauge would be really good, but I'd go no smaller than 14.

 

Or park closer if you can.

 

it depends on the size of the cord or more specificly the size of the wire in the cord

IE...if the cord is 16 gauge wire there will be more draw on where the cord is plugged in and less voltage on the other end which will not provide the proper voltage to the heat resistor coil in the block heater

when you use bigger wire it doesn't draw more amps than normal

yes the voltage drop is very small but is still there

to test this principle there must be a draw on the cord

14 might work but I would say it is safer to use a 12 gauge wire cord it should work like it is supose to all the time.

you don't blow any brakers with that 75 foot cord?

the rule of thumb is to go up a wire size every 100 feet

 

Pretty sure you can get 10 ga in that length...kinda pricey though.

 

havent blown any breakers yet what about time its plugged in. its suposed to be 22 tonight and I havent ran the truck in about 5 days so would 5 hours be long enough or should i leave it plugged in all night.

 

Plug it in about two hours before you want to start it,then everything should be nice and warm and heater should work good after about a mile of driving

 

I'd say anything over 4 hours is a waste of electricity.

I have mine on an outdoor timer and I have it set 2 hours before I leave. Warm enough to make for easier starts on the truck....but if you plug it in for longer you can get it warm enough to read on the temp gauge.

 

I agree with everything except what's bolded. The smaller the cord, the more IT heats up instead of the block heater. It won't draw more from the wall.

Where's the electrician-moderator??

 

will it hurt anything besides my check book to leave it plugged in all night because ive found my timer is broke

 

nope won't hurt a thing.

 

There are a few electricians on here. lol.

It will hurt your wallet a little, overnight for a few nights you will notice. I did down here in FL when the cold fronts come.

As for the voltage/current argument...

The voltage drop for a 100 ft isnt going to be much with a 120/240v Single phase source. The long and short is,the electricity has to travel farther than it should on a lower rated wire. Which creates heat. You need more circular mils but we wont get into that.

The cord is probably rated for 15amps and it will be in free air which helps. Im not sure what the heater draws but its probably close to 20amps. So whats going to happen is the cord will get warm to the touch if its a decent cord. And maybe hot if its not.

I personally think they should outlaw all 14gauge cords especially over 50ft, they probably cause more fires than Xmas lights.

Mega can second that if he wants

 

Dang, I wish I knew more 'bout electricty. I get stuck on diodes and triodes and such.