question

Phil91 avatar image

using 2 x MPPT blue solar controllers into Color GX, confused about readout shown now.

Hi i have 2 x MPPT units with them both connected via VE direct to the Color Control GX panel. with my initial testing i used only 1 x MPPT unit and the icon on the display (battery) showed the correct wattage being drawn from my DC power. I also have BMV702 connected to the color control GX panel and that wattage was also consistent with the readings on the GX display.

Now i have connected my system in full, which is using BOTH MPPT controllers and both into the VE direct connections of the GX. the readings i was getting before (with 1 x MPPT) for wattage is not anywhere what it should be now the 2nd unit is in play.

with nothing but 1 x led light on in my RV connected the system power used to show 3 watts, but now with the 2nd MPPT connected the display GX and also the BMV702 show 30-40watts for same load as before. Even turning all DC loads off the system still shows 30watts (1.2amps) being drawn.

Nothing has changed except i've connected the 2nd MPPT unit which in effect doubled up my PV input. as well as that my initial testing was with 2 x 12v 190ah batteries (in series 24v) now with the full system connected i have doubled the batteries, giving me 24v @390ah. not sure then if this 1.2am (30ish watts) will 'equalize' itself as i dont know what would be drawing that extra 1amp with virtually no DC lights or accessories turned on.

Any ideas ?

MPPT - Solar Charge Controllergx
10 |3000 characters needed characters left characters exceeded

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

2 Answers
JohnC avatar image

Hi Phil.

So you would have run out of VE.Direct ports. Did you simply pull the BMV out of the system and leave the 'DC Loads' box up? If so, this would likely explain it, a 'best effort' calculation rather than BMV truth.

Maybe this isn't so, but please say. The BMV of course can be plugged into a usb port with a VE.Direct to usb adaptor (or one of the mppt's).


4 comments Share
10 |3000 characters needed characters left characters exceeded

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

i have the 2 x MPPT into the color control via the VE direct, the BMV702 is via a usb-ve interface


DC box is on but the watts/amps in the battery icon is what i was believing before to be true. its showed same as BMV702 in power being drawn. 1 light on used to be 3w (its a 3w light) and not its 30-40w showing in the battery icon (on the lcd screen lower left) and the BMV702. doesnt seem to change with more or less loads applied, but it used to when i test initally with 1 x MPPT in the system. so wondering why adding the 2nd MPPT may have changed this. perhaps its all correct, im not victron guru hence why the cry for help :-)


ML is right. Also, you may be interpreting a +ve reading on the battery tile as a draw on your batt. It's actually indicating a charge status. That may change your outlook somewhat..


thanks John yep was assuming current draw was the readings, based on my intial play and setup with 1 x MPPT. im happy all seem good :-)


Matthias Lange - DE avatar image

Can you give us some screenshots of the CCGX?

5 comments Share
10 |3000 characters needed characters left characters exceeded

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.



not idea why pictures are upside down as they arent on my PC pic folder. The blue battery icon shows about 36w with fans and lights on and 33w with just single led light on. with only 1 x MPPT in the system when i first tested the wattage shown in the blue 'battery' icon on the display showed load i was drawing and increased/decreased as i turned more DC devices on/off

I would say everything is as it should be.
The power at the battery(and on the BMV itself) is positiv -> charging the batteries(from the MPPTs).
36W PV - 3W DC power = 33W charging power into the batteries.

If you increase the load the MPPTs brings more power.
91W PV - 55W DC power = 36W charging power into the batteries.

Phil91 avatar image Phil91 Matthias Lange - DE ·

awesome great, i was 'assuming' that was load out of the battery but your explanation clears thing up for me thankyou

Phil91 avatar image Phil91 Matthias Lange - DE ·

awesome great, i was 'assuming' that was load out of the battery but your explanation clears thing up for me thankyou

Phil91 avatar image Phil91 Matthias Lange - DE ·

ML sorry to ask more questions but i've connected my inverter and running small AC unit and as im not 100% sure about the readings i see on the CCGQ the AC wattage, verses solar charging wattage (being lower) but still shows +ve current into batteries . the manual i got with this victron gear shows nothing or explains nothing about the readings, what they are etc etc .. wondering if i dont have the full documentation seeing im asking these dumb questions