Components Required for Dual Battery System?

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DINOZR

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I have been researching dual battery setups. Some people use the vehicle's native charging system to charge the aux battery (via an isolator). Some people, particularly, in Australia, use a DC/DC charger to charge the aux battery. Apparently their vehicle charging systems are either too smart or too sensitive to handle charging duties.

So what's the case with the Raptor?

Aux battery will be AGM. Can I just do the standard setup through an isolator and let the truck charge the aux battery when it's running? Or do I need a DC/DC charger?
 

CoronaRaptor

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On travel trailers, isnt the vehicle charging system charging those agm batteries? I don't even know what dc-dc means?
 

The Car Stereo Company

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there are some vehicles that have a "smart charging" system. i believe the newer tundras fall into that category. this means the system will stop charging the battery once its full. this also means thst if you have an aux battery, it will not charge all the way. thats where the dc/dc charger comes into play. it allows to fully charge the aux battery even if the main battery is fully charged. @FordTechOne might be able to tell us if the 2nd gen raptor has this or not. but my belief is that it does not. so a simple 200 amp isolator could get you setup with dual batteries. but if he says it has the smart charging system, then you will need a more complicated setup requiring the dc/dc converter
 

FordTechOne

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there are some vehicles that have a "smart charging" system. i believe the newer tundras fall into that category. this means the system will stop charging the battery once its full. this also means thst if you have an aux battery, it will not charge all the way. thats where the dc/dc charger comes into play. it allows to fully charge the aux battery even if the main battery is fully charged. @FordTechOne might be able to tell us if the 2nd gen raptor has this or not. but my belief is that it does not. so a simple 200 amp isolator could get you setup with dual batteries. but if he says it has the smart charging system, then you will need a more complicated setup requiring the dc/dc converter

Ford has been using smart charge since the early 2000’s. It uses 2 circuits to communicate with the generator (alternator) regulator; GENCOM and GENMON. Through those circuits, the PCM controls and monitors the charging voltage.

Newer vehicles like the Gen 2 Raptor are more complex. In addition to Smart Charge, they use a generator current sensor and a battery monitoring sensor to determine the charging system strategy and monitor battery state of charge. The battery state of charge is part of the auto start/stop strategy.

The dual battery option on Super Duty just has the second battery wired in parallel; it appears the battery monitoring sensor only reads the primary battery. However, they don’t use a generator current sensor.

I suppose you could try wiring a secondary battery in parallel and see how the system functions.
 
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DINOZR

DINOZR

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Ford has been using smart charge since the early 2000’s. It uses 2 circuits to communicate with the generator (alternator) regulator; GENCOM and GENMON. Through those circuits, the PCM controls and monitors the charging voltage.

Newer vehicles like the Gen 2 Raptor are more complex. In addition to Smart Charge, they use a generator current sensor and a battery monitoring sensor to determine the charging system strategy and monitor battery state of charge. The battery state of charge is part of the auto start/stop strategy.

The dual battery option on Super Duty just has the second battery wired in parallel; it appears the battery monitoring sensor only reads the primary battery. However, they don’t use a generator current sensor.

I suppose you could try wiring a secondary battery in parallel and see how the system functions.

It sounds like a "simple" isolator with the battery wired in parallel may work. I'm designing the system and found the Raptor's alternator is rated for a max of 270 amps (200 amps at idle)! This is far above the ratings for common products used for these dual battery systems like Blue Sea ACRs (smart isolator and charging relay). Do I really need to step up to Blue Sea's 500A continuous/ 700A intermittent model, or will the 120A continuous / 210A intermittent model do?
 

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It sounds like a "simple" isolator with the battery wired in parallel may work. I'm designing the system and found the Raptor's alternator is rated for a max of 270 amps (200 amps at idle)! This is far above the ratings for common products used for these dual battery systems like Blue Sea ACRs (smart isolator and charging relay). Do I really need to step up to Blue Sea's 500A continuous/ 700A intermittent model, or will the 120A continuous / 210A intermittent model do?
it depends on what kind of current you need. are you just charging a battery so it can be used when the truck is off? or do you need additional current for something? what are you powering off the aux battery?
 
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DINOZR

DINOZR

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it depends on what kind of current you need. are you just charging a battery so it can be used when the truck is off? or do you need additional current for something? what are you powering off the aux battery?

I suspect my max load case is if main starting battery is dead and I want to combine batteries to "jump" the start battery from the aux battery.

Normal aux battery duties will be
ARB twin air compressor (50A max)
LED strips for bed lights (3A max)
12V cooler/refrigerator (4A max)
110V Inverter. Still sizing. Thinking 1000W. I have no concrete plans to run anything off this, but while I'm in there, I want to build in a lot of capability. I suppose a 110V power tool might be what I would want to run, like a grinder or buffer.
 
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