Nominal DC Current Draw?

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340inabbody

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Does anybody know what the nominal DC current draw is off the main DC red feed off the battery is with the engine off and the lights on? I suppose what I am asking is what is the nominal DC current draw of the car with the lights on? Note not including high beams only low beams.
 
It all depends on what bulbs you have and the amount of resistance in the connectors and wiring. So not an easy answer.
 
Every car is different. To get the answer for your car hook up a ammeter in line from the battery terminal.
 
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Aw common guys.
I've posted this more than once. Both for diagnosing resistance in a circuit and for planning on loads an alternator needs to be able to supply.
Do a search. I can't stay on this website and risk having it crash my system - which
 
I can't stay on this website and risk having it crash my system - which
Yup. I'm on here a lot less now and reply even fewer times- can't stay on for more than a few minutes or the laptop loads up and freezes. And it's only this site that does it. What a shame.
 
I have an ammeter hooked up. I am troubleshooting some electrical issues. New/rebuilt harness. Car was completely stripped down for paint and reassembled. Lots of variables. Have traced through and solved several issues successfully. Just wanted an appropriate current draw of my halogen lights to see if I am in the ball park. Thats ok Ill work through it and use approximately 10A from Ohms law and go from there.
 
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Yeah, on 40-50 year old vehicles, there is no such thing. Fully restored with a new harness is about as close to nominal as you can get if you're measuring draw at the battery on a headlight system.
 
Ammeter reads 40 discharge to 40 amps charge
With engine oiff, key off, headlights should show about 10+ amps discharge depending on lamp type and whether parking lights go off with headlights on.

Vehicle with H4 lamps and sidemarker lamps


Sealed beam headlights

<snip>
Lets say that nominal 60 Watt lamp was rated at 12 Volts.
12 volts = 5 amps x R, R = 2.4 Ohms
then
14 volts = I x 2.4 Ohms, I = 5.8 amps

solving for the new power at 14 Volts
P= 14 volts x 5.8 amps
P = 81 Watts.

using H4s?
 
Yup. I'm on here a lot less now and reply even fewer times- can't stay on for more than a few minutes or the laptop loads up and freezes. And it's only this site that does it. What a shame.
I'm not getting computer crashes but this website freezes on me on the regular.
 
I'm not getting computer crashes but this website freezes on me on the regular.
To be specific. It knocks the video signal out on my WinPro7 desktop. Sometimes I'll notice slowing in response esp. USB mouse. Anyway lemme log off before trouble occurs
 
To be specific. It knocks the video signal out on my WinPro7 desktop. Sometimes I'll notice slowing in response esp. USB mouse. Anyway lemme log off before trouble occurs
I am sure your computer is fine. It’s just my stupid questions that makes your computer want to pull its hair out. But it ain’t got no hair so knocks your video signal out which is equivalent to pulling hair btw…
 
If the electrical system is stock, the total draw is probably a few amps [ single figures ] less than the alt rating.
 
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