240V Inverter in a Van or Truck

Philip

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#1
I have been researching how to install a big 12V - 240V inverter in my van. Not long ago @WoodsWeapon mentioned a guy on VitalMX who had such a setup. I managed to get a hold of him, but he referred me to his more electrically skilled friend, who actually came up with this installation recipe. Here is the recipe:

RECIPE #1

1) Buy and install a dual alternator kit. Nations Starter & Alternator offer Multiple Alternator Kits The prices range from $650 for popular trucks with just one upgraded alternator to almost $2K for dual upgraded alternators and a regulator for more exotic Sprinter and ProMaster vans. You may want to consider a triple or a quad alternator kit too, hehe.

2) Buy and install a 400W 12V - 240V pure sine wave inverter. Those cost about $1K. This one is a good option: 4000 Watt Pure Sine Inverter Charger - 12 Vdc to 120/240 Vac , and so probably this one: Discount China 4000W Peak 12000W DC24V Pure Sine Wave Inverter With Charger 65AMP LCD Screen - www.sungoldpower.com . I recommend you check their Amazon ratings as well. I like the first one because, apparently, it can provide 110V and 240V simultaneously.

3) Install two deep cycle marine batteries. Four batteries is recommended in order to charge a Redshift from zero. I am not sure on their required capacity, but I imagine the price can be around $1K or so.

4) The guy recommended a high idle kit for the van/truck. It keeps the RPM above the default 700-800 rpm. Apparently the regular low idle still discharges the deep cycle batteries before the Redshift is fully charged. The high idle kit can bump it up to about 1800-2000 rpm while charging.

That's it.
 

Philip

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#5
Some more important details that I almost forgot about:

Two deep cycle batteries is okay, but you really need to get two more to be able to charge from 0%-100% without having to take a break and let the batteries catch up.

WIRE Gauge has to be thick otherwise you are going to burn it up and go through those.

Fusing -- make sure to get the correct ones and sized properly. You don't want to burn anything up.

High Idle kit is key.
 

Philip

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#8
What I do not get is, if I install two 280A alternators in my van, why would I even need any additional batteries? 2 alternators * 280A * 12V = 6,720W. This should be a plenty of power to run all the van's electrical systems and the Rapid charger simultaneously. Why would I need any deep cycle batteries at all?

It looks like the alternators do not really produce their rated power. But even the Hot Idle Amperage @ 200F is 165A. That is still 2 alternators * 165A * 12V = 3,960W. Bump up the idle speed and there will be more power available.

Where does my math fail?

270XP alternators specs: 270 Amp High Output Alternator for 2014-2015 Dodge ProMaster Work & Cargo Van
 

rayivers

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CT, USA
#9
2 alternators * 280A * 12V = 6,720W
Your math seems fine, but are you certain these alternators can be paralleled into a single DC load? I couldn't find anything on point at the site FAQ, but I did see mention of an 'alternator excitation harness' which apparently provides on-demand alternator switching (presumably for separate loads).

Re the battery... I don't think I'd connect any automotive-type 'dumb' battery to a system this powerful without some kind of interface unit, to prevent overcharging or excessive discharge rate.
 

Philip

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#16
don't forget your high idle vehicle will be 'sipping' the petro to recharge that battery bank all day not to mention the wear & tear on your mode of transportation to the track!
Yeah, I remember that. Even with a low idle my van still consumes a lot of gas and produces a lot of heat, which makes standing right outside of it uncomfortable on a hot sunny day. Often a worse kind of uncomfortable than standing near a loud generator.
 

OneLapper

"You don't *really* need the water pump...."
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#17
That 10kw generator is 540 rpm PTO driven (25hp compact tractor minimum). A truck PTO is a different animal, usually much higher rpms to drive a hydraulic pump.
 

Philip

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#20
or what if Alta sold battery packs to refill the bikes battery then you could leave that noisy generator refilling the 'charging' station while your out roosting @Judaslefourbe ;)
Yep. Sounds like bringing a spare charged battery with you is a very attractive option, considering the alternatives. Wish it came with a couple of factory mechanics though to help me swap it.