Quote:
Originally Posted by KenHigg
Seems you have a knack for mods where electrical work is involved. What are you running that draws 70 amps on a 4g wire?!? Do sound systems draw that?
|
My amp (
http://www.arcaudio.com/store?p=90847 ) alone is 90a
A simple rule in audio was to count the fuses x what they are, that's your maximum draw for that device. i.g. Three (3) x 20a fuses is a 60a draw. Input should equal output. Therefore if you add in two amplifiers at 40a x 2, 20a x 3, a processor/EQ/DSP with a 10a x 1 you added current draw is at 150a max draw. But that is best for calculating current draw and fuse selection for protecting the circuit(s) itself.
Sure the battery and type greatly help but in the situation where your Honda Civic alternator is 85a your amplifier draw at full out draws 70a before losing efficiency.. I promise you will leapfrog replacements of batteries and alternators every other year or two at best.
When you are running more stuff in a car the voltage changes with load and heat etc., even with wire gauge being improper will add resistance to the circuit as well mechanical interference's [connections, splices.. ect..] Most people figure their system under Ideal circumstances [Imagine your car sitting in an air conditioned arena just running the amplifier].
Now don't forget to figure in the clipping [audio related] . . . this will cause and increase heat in your gear and it will become less efficient, but since some people can't hear distortion at subwoofer frequencies {80Hz and down to about 30Hz}
And just as you would do for calculating AUX system draw.
The two reserve batteries run all of the AUX lighting (LED bars and Cubes with exception to the under hood LED light strip) in my setup. So for me I had to calculate:
Exterior AUX needs
- 1.5a x 5 LED cubes
- 4.5a x 3 6" LED bars
- 12a x 1 20" LED bar
- 24a x 1 40" LED bar
Interior Flip-Pac AUX needs
- 1.8a Flip-Pac interior lamps [includes 4 small LED bulbs]
- 3.2a x 1 for Electric blanket use
- 4.7a x 1 Dometic refrigerator
- 2.8 x 2 Camera Battery chargers
- 2.5 x 2 Laptop chargers
- 1.2 x 2 USB Flashlight chargers
- 2.1 x 2 USB AUX ports for charging devices
Which gives me a total of about 85a [83.9a to be to spec]
Now I dont need to run all of that and if I only used 2/3 of the interior AUX needs I have about just under 32 hrs of autonomy in my setup that I dont need to a.] Start the truck b.] Plug in to 120v shore power c.]Throw the solar panels in the sun. There's a ton of minimalist features in my setup to get what I need in power for long(er) term off grid like lil adventures.
My setup charges the main battery first when it reaches a specific voltage indicating a full charge, then it charges the secondary batteries. Should I somehow kill the MAIN/Start battery. I can flip a switch and pull current from all three batteries to start the truck up and the truck will charge the main battery again before topping off the AUX batteries.
There is a bit to consider whatever your goals may be for.