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S_Davis's avatar
S_Davis
Explorer
Nov 05, 2017

Inverter AGM questions

I have been thinking about installing a inverter in my truck, either a 2000-3000 watt. I would use it to run small power tools, air compressor, an electric blanket when on the ferry system as you can't run your vehicle. I would also like to set it up to power a truck camper when we purchase one in the next couple years. What I would like to do is remove my rear seats in my crew cab and build a storage box that would house two to four AGM batteries and the inverter, I want to install a 12v plug in the bed to connect to the camper batteries to form a larger battery bank as well as a 120v outlet to power a microwave, coffee pot, hair dryer. Will it work, is charging AGM batteries from the truck an issue?

147 Replies

  • Make sure the wire from your alternator to the new battery bank is as large as you can find / afford (minimum 4 gauge.) The alternator is setup to charge the engine battery through a 2-3 foot cable, so it will charge first/fastest, and the extra batteries will never top off, since the alternator cannot sense the other batteries being weak at the end of a long skinny cable.

    X2 on previous suggestions for an isolator, to protect your engine battery from being used while the engine is off.

    Regarding connecting trailer batteries to the in-truck batteries, well... it's possible, but why? It isn't going to work like you think, as one large battery bank. You could buy a bank selector switch, and use either the in-truck batteries or the trailer batteries.
  • In answer to your question about the AGM batteries being charged by the truck:
    No problem if you have a heavy-duty alternator. That's what my Tiger has (Chevy 2500 HD) and it charges two Lifeline 6V AGMs in the camper part of the rig just fine whenever the truck engine runs. Thick wires. Shortest run possible.

    Does your plan call for some sort of battery isolator to keep the extra battery bank from draining the truck battery? It should.

    I cannot answer your inverter or TC questions. Sorry.
  • This is one of the inverters I was looking at.

    http://www.xantrex.com/documents/Power-Inverters/Freedom%20X/DS20170322_Freedom%20X.pdf
  • Need sine wave with most electric blankets and is better for motors in power tools. 2000 watts is plenty to power anything that plugs into a regular outlet. I would stick with 12 volts to allow the alternator to charge the batteries. Still need a good battery charger during moderate to heavy use to bring the batteries back to full charge.

    GP inverter $825

    2 to 4 Lifeline batteries: http://lifelinebatteries.com/products/marine-batteries/gpl-31xt/

    IOTA IQ DLS-30 charger $150

    Custom 12v cables http://www.genuinedealz.com/custom-cables

    Good luck
  • My concern on the connection is that when you're powering big loads like MW, I'm not sure the extra battery connection will help much. The wires need to be big and fat and short...at least at 12v they do. Now, if you wanted to step up to say 36v, it might be more feasible.
  • 2oldman wrote:
    S Davis wrote:
    .. install a 12v plug in the bed to connect to the camper batteries to form a larger battery bank as well as a 120v outlet to power a microwave, coffee pot, hair dryer. Will it work, is charging AGM batteries from the truck an issue?
    Will the 12v plug serve to make a larger bank to power the inverter?

    AGM batteries work fine in my truck.



    That is kinda the plan, and the 120 plug would power the camper with the converter turned off.
  • S Davis wrote:
    .. install a 12v plug in the bed to connect to the camper batteries to form a larger battery bank as well as a 120v outlet to power a microwave, coffee pot, hair dryer. Will it work, is charging AGM batteries from the truck an issue?
    Will the 12v plug serve to make a larger bank to power the inverter?

    AGM batteries work fine in my truck.

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