When do you need a bigger alternator or second battery

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PorterW1111

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Wondering at what point one would consider the need for a second battery and or bigger alternator.

I’m running 10 40w up front and 8 60w up top. It is very rare that they are on, and with that even more rare that both are on at the same time. But curious if someone loaded out all 4 upfitters would the truck be able to support without an issue based on factory design or should(need) I bump up to the bigger capacity?

they both don’t go on at the same time cause who really needs ~75k lumens ....

Fronts are ambers spot/flood top is white spots.
 

PlainJane

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The upfitter switches are not the limiting factor, you should be running relays on those circuits. Your lights are 880 watts and from what I can tell, we have a 200 amp alt. that 2400 watts.

A second battery is always nice, especially if you use the inverter very much or install a larger one.
 
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PorterW1111

PorterW1111

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The upfitter switches are not the limiting factor, you should be running relays on those circuits. Your lights are 880 watts and from what I can tell, we have a 200 amp alt. that 2400 watts.

A second battery is always nice, especially if you use the inverter very much or install a larger one.
Tracking. The only circuit not on a relay are the fog lights only a 6.5 amp draw on those. Thinking the 4 up fitters are “labeled” for their intended amp draws because that’s what the truck can support? You say we have 200 amp alternators but what is the truck using at any given time? If combined my lights are pulling ~75amps, is there any risk of “stealing” from the truck?

practically zero inverter use.
 

The Car Stereo Company

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you are fine. most amp and sub installs we do use a 1000 watt amplifier so as far as current draw goes, with all your lights on at once will equal that. i have 2300 watts in my stereo, 110watt vhf, 3 40in light bars 14 cube lights, and the disco raptor. way more current than anyone else. still stock alternator. i did add a second battery in my bed because i have 4 air compressors. but everything isnt on all the time. i do run my vhf and all my lights when running events which is more draw then what you have and 7 years later, still working fine.
 
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PorterW1111

PorterW1111

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you are fine. most amp and sub installs we do use a 1000 watt amplifier so as far as current draw goes, with all your lights on at once will equal that. i have 2300 watts in my stereo, 110watt vhf, 3 40in light bars 14 cube lights, and the disco raptor. way more current than anyone else. still stock alternator. i did add a second battery in my bed because i have 4 air compressors. but everything isnt on all the time. i do run my vhf and all my lights when running events which is more draw then what you have and 7 years later, still working fine.

lol all I can hear from this reply is you laughing at my baby current draw compared to your monster setup bahaha

Thanks this significantly reduces my concern. Ill go back to the kids table now hahah
 

richnot

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The only reason I have ever had dual batteries was for the Winch on my Jeep, it had a mode that would bump the idle up while using anything that pulled a lot of amps from the system.
 

Raptor 2014

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You are approximately 73 AMPS when all the additional lighting is on - Lots of additional drain but you are Good to go.

I thought about running an additional alternator just for reliability like an ambulance for an Alaska trip in the near future but haven't screwed with it yet - probably won't

A second battery is always nice - Set up with a battery isolator so you don't drain your main battery when your ignition is off.
I currently have a 6 ton winch - (Huge battery drain), currently 40 or so additional exterior lighting amps and a 2000 watt pure sign wave inverter, ARB dual air compressor connected to a 3 gallon aluminum under bed mounted tank all hooked up to (1) ignition off or (2) ignition on group 31 lithium ion Batteries bed mounted all being charged though stock alternator - No problem so far with the charging capacity - 2014 Raptor
The alternator will be charging my trailer soon also when on the road - 2 additional group 31 lithium ion batteries. Will use a solar charger when parked.
 
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