Need some help calculating potential series or parallel circuits.

Combat squirrel

Combat squirrel

Combat squirrel

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Hey all.

I have a small camper van with an All Powers S2000 Pro power station - it has an XT60 input for charging from multiple sources (solar or van cigarette plug)

It's spec for this input can be 18-70 volts at 18 amp max

I Have the 2 following power sources that feed power at variable rates:

Van - 12.9v - 10 amps

Solar - 22V - 8.61 amps (180 watt panel)

I'm wondering, would it be possible to wire these 2 inputs in a series or parallel plug to feed more power into the power station.

Both power sources fluctuate - when the van is accelerating it reduces power from its 12.9v cigarette port & puts out more power again under free wheeling (up to 14.7v) (I've monitored this on the all powers app while driving), solar obviously various constantly.

I'm thinking series would be the best way to wire this, given the power station has a large variable voltage tolerance ? Am I wrong? Will this idea fail ?.............how will the circuit behave with 2 different fluctuating voltages and slightly different amperage ?

I'm only thinking it may work as the power station can apparently tolerate a wide range of power - however I'm not sure if it knows its attached to a generic solar panel or not (and thus I'm not sure if its using solar tracking) or if it just takes and processes whatever volts or power happens to be going into it.
 
Just tried to calculate / work this out:

If in series it will be approx 35 volts - at whatever the lowest Amps are detected at that time?

35v, 8.6 amps, approx 300 watts of input power with a slight 5% loss in efficiency (because the circuit will drop to the lowers mixed amp?).

I sort of think the power station doesn't know a solar panel is attached it just picks up whatever is fed in - is this right ?
 
Combat squirrel said:
Now im concerned that maybe the solars 22v may 'leak' back down the 12v wires from the cigarette plug - which isn't good, would it do that?
Click to expand...
The cigarette plug is usually fused with a 10 amp fuse and it can possibly damage your electrics on your camper van if you connect a 22v solar panel to it. As your sending 22v straight to the camper van's battery and electronics. That even if you connect the battery and solar panel in parallel or in series (please correct me if am wrong).
Combat squirrel said:
I sort of think the power station doesn't know a solar panel is attached it just picks up whatever is fed in - is this right ?
Click to expand...
The power station usually has some sort voltage sensor inside that will charge when it see that voltage range in this case 18V-70V.
 
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If you connect multiple solar panels/cells in series, if one is shaded and has reduced current, this limits the current in the entire string. So I suspect you'll have a similar issue with the solar panel in series with your van output.

I also think it's pretty dodgy putting two independent devices of separate voltage ranges (neither is fixed, voltage will fluctuate) in series.

You're proposing to end up with a system that has one source of current that is reasonably stable but attached to a van so could be sensitive to overcurrent etc, and another which will have a wildly variable voltage and current capacity from moment to moment as clouds pass etc. Then you're proposing to attach a reasonably complex management circuit that will be trying to hustle that variable voltage into the desired current to charge itself. It seems both unwise and also hard to predict what will go wrong if/when it does.

Is there any chance this kit is available with multiple inputs? Or can be switched between solar and battery manually?
 
Combat squirrel said:
Now im concerned that maybe the solars 22v may 'leak' back down the 12v wires from the cigarette plug - which isn't good, would it do that?
Click to expand...

Definitely don't do it without a proper combiner with diodes and fuses, etc. but even a basic combiner for solar/wind is not really the way to do this.
 
You can't connect them in series, the series resistance of a solar panel is quite high.

The lazy way is to wire them in parallel with a blocking diode to stop current from the solar panel going into the van electrics, 22V may damage things in the van.
 
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