Nominal DC Current Draw?
- Thread starter 340inabbody
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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'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
Professor Fate
Push the button, Max...
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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jos51700
Green Bearing thread connoisseur
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
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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?
www.candlepowerforums.com
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
67 Barracuda alternator with 2 FLD connections
The PO of this car and his junkyard parts are driving me nuts. He also played with the wiring. The alt that came with the car has 2 FLD connections. Both had wires, but on this car, that doesn’t mean anything (about to go chase the wires through the harness). The rebuilt alts I see online, my...
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Charging circuit - reduced load on ammeter circuit
67Dart273 PM'ed me about this thread as he recalled mine linked below. The dual diodes allow your dash ammeter to still work at lower currents, but shunts progressively more current straight to the battery at higher outputs. The ammeter is intended to read all current flow in and out of the...
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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?
Interesting headlight bulb test results
As part of a larger project, I needed to run photometric tests with different bulbs. All lamps and bulbs were run on the same goniophotometer, on the same power supply set to 13.5v. I can't share the entirety of the data, but here are some of the highlights from four bulbs tested in two new H4...
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I'm not getting computer crashes but this website freezes on me on the regular.
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…
Bugman
Well-Known Member
Bugman
Well-Known Member
Check for voltage drop too
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