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As I continue to plan the van, I have more questions about the electrical system. I think I'm going to go with a separate inverter, separate charger and separate transfer switch. Here is the plan as it sits right now (could change in 15 minutes)

Progressive Dynamics Lithium Charger
Samlex 30amp Transfer switch OR Xantrex 15 Amp Transfer Switch
Xantrex 2000w inverter

This comes out to around $750 where the base price for an all in one unit that can be programmed to charge lithium is around $1200.

My question is about Shore Power hookup type. I was originally thinking about using a 15amp plug, but I I'm not sure if I might need a 30 amp. The 60amp lithium charger uses 1000watts (Here is the info on the chargers). If I'm on a 15amp shore power, if I'm charging the battery and then turn on my 1500 watt electric kettle, wouldn't I trip the breaker? The literature says "Low line Voltage protection Automatically shuts down converter if input voltage is insufficient" However if I turn on the cooktop after the converter, wouldn't the breaker trip before? Is there a method to turn on or off the battery converter/charger? Could something like that be wired to a switch? The battery charger/converter would only run when hooked up to shore power.

Also since I'm so new to camper/rv stuff, does the converter/charger also supply power to the DC loads when plugged in, or just charge the battery and you are still powering devices off the battery?
 

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Seems you've already answered your question, go 30 amps. Why not? At most you'll need a 30-15 amp adapter. This gives you options - - in our case we anticipate running an electric space heater while on shore power - - that, alone, would max-out a 15amp circuit.
As I was typing this thread, I kind of came to that conclusion, but was hoping someone would chime in and give me some info I wasn't aware of.
 

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You have some sophisticated hardware. Several here prefer 15A but you may want/need air conditioning in the future so go with 30A. No harm and little additional cost.
 

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....cut....

Also since I'm so new to camper/rv stuff, does the converter/charger also supply power to the DC loads when plugged in, or just charge the battery and you are still powering devices off the battery?
This is essentially a distinction without a difference. Electric power will flow to where it's needed, so if your converter was putting out 50 Amps, and your devices were using 20 Amps, the remaining 30 Amps would flow into battery. Likewise, if your devices suddenly exceed the converter's output, the required additional current would come from batteries. This is a simple way to look at it.

The battery is for the most part a current accumulator. It's not 100% efficient but does a good job of storing electric energy to be used at a later time. Lithium batteries are typically more efficient than lead-based batteries because they have less internal resistance. Basically it means current or energy can flow in and out easier than with flooded or AGM batteries.


Regarding 15-Amp service, in my experience most campgrounds have 20-Amp breakers, not 15s (if that makes a difference). With normal voltage that's good for 2,200 to 2,400 watts -- which can be a lot for a small camper. In a case like yours (and mine) I think it's better to have more and not need it, than need it and not have it. For that reason I have 30-Amp electrical. I can run space heater and microwave at same time plus TV and charge phones etc. In 10 years I've never tripped a 30-Amp breaker with my van.

I also carry an adaptor and heavy-duty extension cord in case it's needed. I've only connected to 20-Amps a few times and don't recall tripping the breaker.

For what it's worth, I have tripped 30-Amp breakers a couple of times when camping with Class C motorhomes. Typically it involves air conditioner, microwave, and hair dryer at same time. You'd think we would remember that that combination can't work. :)
 

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P.S. -- A 20-Amp extension cord isn't easy or cheap to get. My backup is rated at only 15 Amps so when plugging to 20-Amp receptacle I usually use an adaptor and 30-Amp cord. I'll use the 15-Amp cord if I know I will be pulling little power. The 15-A cord is much lighter and easier to handle than 30-A cord, but that's such a minor difference.
 
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