Inverter AGM questions

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.

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.

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.

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

This is one of the inverters I was looking at.

http://www.xantrex.com/documents/Power-Inverters/Freedom%20X/DS20170322_Freedom%20X.pdf

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.

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.

Understand too that (whether sine wave or square wave), when it comes to power tools and pumps, all seemilgly equivalent 2000w inverters are not the same... Electric motors are reactive loads, thus what must be considered is the nominal wattage of the load along with an imputed 4-5 times that amount that occurs briefly upon motor start-up.... Inverters see reactive loads vs resistive loads (like a hair dryer...) quite differently...Depending on the size of this load, some inverters of same advertised ‘like wattage’ (say, 2000w) may not be able to handle a high amp motor (particularly pumps and compressors) due to the initial start-up surge that must be overcome...

In your application, beyond advertised wattage I would also be interested in knowing the inverters surge rating and over what time period in seconds or milliseconds....Often this information is sometimes not published or can be hard to find, but knowing this can help avoid a costly repeat purchase of a different model...

The higher and longer the surge rating, the costlier the inverters electronic componants, thus bargain inverters need to be judged accordingly.... I agree that PSW is more efficient for the run requirements of electric motors....

Battery cable wire gauge and short lengths of cable runs iare also important - Larger is better (I’m running 4 ought, or 0004) ...

Hope this helps

3 tons

AGMs can be expensive and the OP will prolly want to maintain them well. There's a ongoing discussion of just that here: https://forums.goodsamclub.com/index.cfm/fuseaction/thread/tid/29469100.cfm

pnichols has some interesting comments there about fully charging them, in part with his alternator, and monitoring their charge current to do so.

Does the OP plan to charge these AGMs with anything other than the truck's alternator?

Love the idea of packing the back of a crew cab with batteries. :)

I would want to put the batteries into a sealed space that was vented outside the truck.

I'd buy a hybrid inverter/charger, such as Victron.