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Do I need more amperage?


lucasruble

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Just got me a push bar with some lights included from the wrecking yard I work at. I was wondering if I need to get a higher wattage alternator to keep up with the demand of (hypothetically/if needed) running fogs, h.i.d. heads, the new floods, and the usual electronic drain (stereo etc...). If I do need to get a bigger one, what wattage will be sufficient?
 


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lucasruble

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No helpy? : ( Helpy now! : )
 

Spott

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Alternators are usually rating in amps. If you know how much current (amps) each device draws, just add them together and see what you come up with. You should get an alternator that's at least 1/3 bigger than your maximum draw.

If you don't know the current for a device, but you know the power (watts) you can divide the watts by 12 to get the current for that device.

Let me know what you find,
Spott
 

06RangerXLT

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hids use about 2 amps or less, fogs are nothing, if you notice your lights dimming when you come to a stop, upgrade. if not your good.
 

lucasruble

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Thanks Spott and 06RangerXLT. I didn't know lights were so low in amperage. I probably shouldn't have to worry about it. Although, sometimes, when I have my heads on and turn the blower up full blast, my charging gauge takes a dive to about twelve volts or so. This is at idle. As soon as I start going, the needle shoots back up to around fourteen volts. Not sure if this is normal. It doesn't happen all the time.
 

06RangerXLT

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Thanks Spott and 06RangerXLT. I didn't know lights were so low in amperage. I probably shouldn't have to worry about it. Although, sometimes, when I have my heads on and turn the blower up full blast, my charging gauge takes a dive to about twelve volts or so. This is at idle. As soon as I start going, the needle shoots back up to around fourteen volts. Not sure if this is normal. It doesn't happen all the time.
12 volts is still suitable. its when it hits like 8-9 volts, that you wanna watch out. if you have a hard time starting the truck, you could try a better battery, but it sounds like the alternator is doing itf job when you get back up to speed.
:icon_cheers:
 

Bob Ayers

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12 volts is still suitable. its when it hits like 8-9 volts, that you wanna watch out. if you have a hard time starting the truck, you could try a better battery, but it sounds like the alternator is doing itf job when you get back up to speed.
:icon_cheers:

12 volts IS NOT GOOD! At that voltage, the battery is being discharged!!

But what do you expect from somebody that thinks e-fans are good!! :headbang::headbang:
 

Spott

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A fully charged battery is ideally 12.6 volts. With the engine running, the voltage should ideally be 13.8 volts, under all conditions. But we don't live in an ideal world...we live in the real world.

I'd double-check the voltages with something more precise than the dashboard voltmeter, before you jump to any conclusions.

Spott
 

Bob Ayers

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A fully charged battery is ideally 12.6 volts. With the engine running, the voltage should ideally be 13.8 volts, under all conditions. But we don't live in an ideal world...we live in the real world.

I'd double-check the voltages with something more precise than the dashboard voltmeter, before you jump to any conclusions.

Spott

A drop of 2V on his meter is a good indication he is measuring the battery voltage, which is then in the discharging state.
 


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