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Altenator isolator
Hello, I am creating an off-grid power option with my 2018 Crosstrek. Autozone just tested my battery and alternator-output was 12.8 to 14.
I will have an auxiliary 100aH AGM deep cycle battery with a 2000 w inverter but am curious about the vehicle battery output not discharging enough... (due to the Crosstrek possibly having a smart alternator?) to allow voltage needed to power the auxiliary battery? Has anyone experienced this or any advice would be appreciated? I am 100% novice getting my masters through YouTube =-*
Thanks a bunch. =]
~馃
 

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Yes the Crosstrek has a "smart" alternator. Voltage drops and the battery is under-charged. In my 2018 I am monitoring system voltage and find the voltage bumps up to 14.4 when a larger electrical load is added, such as headlights, aircon, or turn signals. With low electrical load such as low fan only, the voltage is around 13.5. With no electrical load added the voltage is 12.2, which is battery only.

if you intend to charge this deep-cycle battery while driving, you will need to turn on electrical stuff. Perhaps always drive with headlights on. It is unknown to me if the smart alternator detects an actual load (I guess not) or if the brain sees switches are on. You can add a cheap voltmeter in your vehicle to see what is going on.

You need to research the power/current specification of your alternator to be sure it can provide the needed juice to your deep cycle battery. You may need to include a dedicated charger/tender for it, not just wire it to the alternator.

Power isn't free. You will burn gasoline to charge that battery. You may get off-grid but it won't be zero emissions. Even solar has environmental impacts of the manufacture and eventual disposal of the equipment.
 

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2021 Crosstrek Sport
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Altenator isolator
Hello, I am creating an off-grid power option with my 2018 Crosstrek. Autozone just tested my battery and alternator-output was 12.8 to 14.
I will have an auxiliary 100aH AGM deep cycle battery with a 2000 w inverter but am curious about the vehicle battery output not discharging enough... (due to the Crosstrek possibly having a smart alternator?) to allow voltage needed to power the auxiliary battery? Has anyone experienced this or any advice would be appreciated? I am 100% novice getting my masters through YouTube =-*
Thanks a bunch. =]
~馃
Did you ever get this setup?
 

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2019 Canadian Sport trim (6MT // 2.0 )
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Yes the Crosstrek has a "smart" alternator. Voltage drops and the battery is under-charged. In my 2018 I am monitoring system voltage and find the voltage bumps up to 14.4 when a larger electrical load is added, such as headlights, aircon, or turn signals. With low electrical load such as low fan only, the voltage is around 13.5. With no electrical load added the voltage is 12.2, which is battery only.
Which year/trim? I monitor my voltage on a nearly daily basis, including long trips, and it's dead steady at 14.x V. Never has it dropped to battery level on mine
 

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Which year/trim? I monitor my voltage on a nearly daily basis, including long trips, and it's dead steady at 14.x V. Never has it dropped to battery level on mine
I've seen ours drop. I also have some charts from our BT monitor. I know I sound like a broken record but we haven't had one issue since we got the Odyssey AGM...
 

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I've seen ours drop. I also have some charts from our BT monitor. I know I sound like a broken record but we haven't had one issue since we got the Odyssey AGM...
I concur this, seems the alternator will not charge on higher voltage if the load is minimum or battery voltage is already quite high
 
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