Charl Joubert

The Imp on the 1st MPPT should be ok, the Vmp, does not give us Voc, which is important...


According to the spec sheet, your Vmp is within the MPPT range, but I'd still be worried about the peak voltage, when no current is being consumed and its a cold day, wherever you are... at 45.2V Voc times 16 panels, you'd be at 723.2V outside the MPPT specs, still within the PV input range, I don't suggest this is good setup. I'd suggest 15 or even 14S would be safer numbers in terms of Voltage... this is now the problem, the panels coming out have current figures that don't match up nicely with most of the inverters out there, and going for the near 1kiloVolt MPPT tension is looking for trouble...
Either way, you need to work out what the lowest possible temperature your location is likely to see and with that in mind figure out what that would mean for the Voc and therefore for attempts at letting the inverter produce some of that magic smoke...
 

I have an update (spoiler - I "fixed" it).
After lots of back and forth we finally came to the conclusion that we had to bridge the Smart Load as well but that was making matters worse whenever a geyser kicked in.  Here's what I did, in this order (and yes I followed shut down and start up procedure correctly every time):
Physically:
Unbridged Smart Load - Still had grid draw. Settings:
Made the slave solo and turned off the master - No grid draw. Made the master solo and turned off the slave - No grid draw (this was a surprise). Swapped master and slave in parallel - grid draw. Swapped back to original master and slave paralell config - grid draw. Factory reset (9999) everything and reinstated original parallel - grid draw (but less strangely). At this point I wasn't sure what to think so I added Smart Load settings and schedule back, gave it 60 seconds to kick in, then switched the working mode to Zero Export to CT and SUDDENLY the grid draw went away.  I was now angry because I had been switching between CT and Load mode before and it made no difference!  I was very scared to actually touch it now that it was correct.  BUT I had to rebridge the Smart Load.  So I shut everything down, rebridged it, booted it all up, and still... no grid draw.
So now I have my two inverters properly parallelled and both supplying Smart Load to my geysers without unecessarily drawing from the grid.  Here are some pictures for the curious:

Compared to a usual day where grid draw was happening:

And here's my software version:

I'd like to share my experience with my aux port (Smart Load).
I think that the main reservation behind it is that there's a lack of experience with it in general.  Also to wire it up is a proper mission since you have to totally divorce whatever is wired to it from the rest of the house or it causes issues.
I've personally had my six geysers put onto Smart Load purely to force them to use the sun and leave my battery alone at night.  I think if I wasn't on a parallel system it would work perfectly fine (We still have some kinks to work out and are converting some to gas).  I have also sometimes turned on the "On when on grid" function to force it on when I have a lot of guests.  For me it's meant the difference between 2kW draw and 20kW draw and my one battery lasts a lot longer at night.  I can now even pick and choose which one runs:

So for your case I definitely recommend it, but find yourself a brave... no brave is the wrong word... a determined electrician who is willing to do the leg work and wire things correctly.  If you so much as share a single neutral it's a bugger up (which we had in my case).  The electrician I had actually popped one of my aircons.

I took a drive to Sunsynk SA.  Funny they're about 5 minutes from my house.
I spoke with one of their experts.  The guy tells me that if I'm going to use the aux port then everything must be paralelled INCLUDING the aux port.  So my installer is going to come back at some point and we're going to bridge them and see what happens.
I'll report back when the smoke clears 

They responded within about half an hour.  It's quite scary how you just have to give them a serial number and bam, they've got you.  The language barrier wasn't that bad at all either.  For my specific case it took a day or two for her and the engineers to figure out what was wrong but once they figured it out they were able to give me the right version number.
I'm planning on getting a 2nd battery and just going to plonk the things onto Island mode.  No need to worry about all these little wattage leaks.

Cudos to the Deye inverters. I saw someone running one without setting the parallel operation correctly and there was a loose connection on the one phase. Nothing blew up... but rather make sure everything is normal before closing breakers.