Wiring Configuration

[Tucker]

My Solar system consists of:
(2) Midnight Classic 250. 
(2) us3000 Pylontech Lithium Ion Batteries
(1) SMA Sunny Island 6000 Inverter
(20) Solar Panels.  (2x10)

My question is two fold.
1.  What wire configuration do I use to connect the Solar panels to the two Midnight Classics. And from the Classics to the  Two Lithuim Ions, and from the Lithiums to the Inverter?
2.  The Midnight Classics I have, only have one Comm Port each.
(No idea why).
How do I use Follow Me for the Classics?  Or am I okay to not use this feature?
Thank you for your instructions.

[boB]

Hi Tucker.

Looks like you have Classic 250s that came from the DC Solar auction a couple of years ago.  Those did not have some options that we did for them to save money.  They ended up in the marketplace.  Unfortunately, the extra MODBUS connections and I *think*, Ethernet is not on those units.

Other than that, the MNGP remote jack, which is being used for that function, could be used to talk with a BMS for battery but software would have to be done for that.  That could be done with a Raspberri Pi or some other single board computer.

For other questions, you can call us and ask for support.

PV connections and battery should have breakers etc for disconnecting and especially for battery side protection from short circuits.  It's the batteries that have dangerous current if something bad should happen.

The PV minus and battery minus can share the same connections since they tie together inside the Classic at the battery terminals.

Others can chime in here, hopefully with some other ideas.

boB

PS.  Very nice looking system so far from your picture !

[Tucker]

Thank you boB for your reply. 
I still need a little help connecting the two Classics to the two Pylontech’s.  Where I get confused is
How to connect both Classics to both batteries, and then to the Inverter.  Do I connect one classic to one battery, and the other Classic to the other battery?  I’m just having a hard time picturing this.
Thanks for any help you can give.

[littleharbor2]

 As to your first question and in a nut shell,

Charge controllers cant share PV arrays. You need to find the most sensible way to create separate arrays dedicated to their own controller.

As to making all the interconnections you need to add bus bars to the system all components connect to your bus bars.

[boB]

Yes, each Classic's battery connections connect to the same battery.  Plus and minus.  However, do NOT forget to use a circuit breaker on the battery plus line for each Classic !   This also works as an on/off  battery "disconnect" switch.  Plus side of the DC circuit breaker goes towards the battery if it is polarity sensitive.

Mostly all of our distributors have DC circuit breakers for protecting the wires connecting from charge controllers and inverters to the battery.

There is typically also a LARGER circuit breaker from battery to the connection box (E-Panel for instance)  but at least put a breaker on each controller + line.

boB