Planning for a future upgrade...

[galladanb]

Let me ask a hypothetical question, PLEASE...

If I order this kit first, https://www.amazon.com/dp/B00F865DS0/ref=olp_product_details?_encoding=UTF8&me=

Then I order a smaller 100w suitcase system, https://www.amazon.com/dp/B00DCEKKQ0?psc=1
can I simply use alligator clips to attach and add the suitcase to the existing installed system.

In other words, I am wanting to go ahead and buy, install and use the first kit as the primary system.
Then I want to use the suitcase to supplement and use when ever the van is parked in a shady setting,
and have the suitcase also assist in the recharging efforts.

I know that if I were to install all 3 100w panels in use at the same time I would need a 30a controller, right?
But, I'm wanting to use the suitcase when the van might be parked in lower sunlight and even as a
booster system whenever I need a faster recharge?

Does that make sense? I think I'm asking for the best of both worlds...

I'm not really looking into a lengthy discussion as to why or why not, simply would it work?

Also when using both controller types, which one would go onto the primary system, and which one into the
suitcase system? Is their an advantage in having the MPPT as the primary, or as the suitcase?

 

[Optimistic Paranoid]

With Morningstar MPPT controllers, if you want or need to use more than one, there is a separate doohickey box that both controllers need to be plugged into.

That makes me wonder if trying to use two different type controllers (mppt and pwm) and two different manufacturers is a good idea.

I'm planning to do something similar, but I plan to have only one controller, large enough to handle both the fixed and remote panels.

Do note that I'm NOT saying that it's can't work your way, I just don't know.  Maybe someone here is doing it and can tell you if it will work.

 

[John61CT]

Not a direct answer but hopefully helpful background and example.

The output from the controller is too low at nominal 12V to send any distance without very heavy cabling, or energy loss.

Best would be all your panels out in the sun, no partial shading, IN SERIES to get high voltage, send THAT over smaller (cheaper lighter) cabling to a single controller designed to handle that high voltage, located near the 12V bank being charged.

Better than lugging heavy battery out along with the panels.

Victron BlueSolar line, example 150/100 model, first # is volts, do not exceed, so if 18v each, can stack six panels in series safely.

Second is amps, each panel could in theory be 16-20, if this is exceeded a bit NP, you lose a little peak output but gain more average, overcast etc.

Your case select a lower/cheaper model, but account for future additions.

You have with this line the optional ability to customize output charging setpoints, and get realtime monitoring from your phone.

 

[highdesertranger]

short answer, yes it will work. highdesertranger

 

[galladanb]

THx for the replies...

Maybe I should ask the question a different way...

With a 20a MPPT controller, can I start with 200w panels and then add a third 100w panel in the future,
but use the new one as a portable, not roof mounted?

Will the 20a controller allow for 300w, 200w now and 100w added later?
Then will I simply alligator clip or Anderson pole the third one into the existing system when I need it?

 

[Optimistic Paranoid]

Will the 20a controller allow for 300w, 200w now and 100w added later?

Looking at the specs on the Renogy Eclipse 100 watt Mono panels in your first kit, Renogy says the Optimum Operating Current on each panel is 5.70 amps and the Short Circuit Current  is 6.10 amps.  So yes, a 20 amp controller should be able to handle three of them.