Solar question

I have two separate roof mounted systems, one is MPPT (300w), while the other (retrofitted) is PWM (140w), and they work fine together without any conflicts...Each system has its own output ammeter, and I've added a separate LinkLite whole system meter to verify the combined outputs... All meters reconcile, go for it!

3 tons

Almot wrote:

Yes. But there is no data communication in low-amps controllers like the one he has or the one that comes with a small portable.

OTH, setting setpoints identically would not be possible either, - there isn't much that can be set in these units.

the reason I have the 10A controller that comes with the mentioned suitcase it because it has both features.

your portable bias is showing, again.

KD4UPL wrote:
With many brands if you have more than one controller you can connect them with a data cable so they can communicate with each other.

Yes. But there is no data communication in low-amps controllers like the one he has or the one that comes with a small portable.

OTH, setting setpoints identically would not be possible either, - there isn't much that can be set in these units.

When I look at the cost of this portable suitcase - he will likely pay more than if added another 100W to the roof and upgraded controller to 15-20A. Benefits - not sure. Crocodiles on battery... Battery compartment open to let the cable in... Waking up in the night when it topples down in wind (makes surprisingly loud bang when it does)...Tying it up for wind.... Monocrystalline... Meh...
More sun when parked in shade, yes. If cable is long enough.

Its the same as a solar charger and shore power charger. Mine play just fine together.

~DJ~ wrote:
Any truth to that?

NO, but do ask why.

Enjoy your portable suitcase and all it's portable uses.

It will work. I've installed many systems with multiple charge controllers but they've all been the same controller. I've never tried one with multiple different controllers. With many brands if you have more than one controller you can connect them with a data cable so they can communicate with each other. Blue Sky, Outback, and Xantrex I know offer this. I think Morningstar does too. This would be your best solution.

In real life scenario they will work - somehow.
Work fine - I doubt, unless they are identical, set up identically, and wired identically.

I would add another 100W panel to the roof and upgraded the existing controller (if necessary). In terms of roof space, TC are good for 250-300W total, provided the cable to controller is adequate. For those occasions when you are parked in permanent shade, you can indeed carry a portable, for use when roof panels don't work.

oooooooops! double post

~DJ~ wrote:
I have 100 watt system with a Morning Star controller on my TC. I was thinking of getting a portable 100 watt suitcase type with it's own built in controller by Renogy that I could use on a lot of other things too. But a guy told me that I can't use it with my current system on the TC as it will mess up the controllers. Any truth to that? Thanks............DJ

No, they work just fine together.

I have used up to three controllers on the same bank. They were all the same and set a like.I have also used two different MPPT controllers and BFL13 has used PWM and MPPT together.

Now when I do two or three matching controllers, they are all set alike and have the same length run to the battery. That way they all see the same voltage. You will need both controllers looking to do the same thing and see the same thing.

With the distance and size of wire on the portables I think it may see a lower voltage than the closer controller will. That may take some effort to get perfect by adjusting the set points to switch to float at the same time.

I like having my portable to keep things charged up around the house.