DC to MPPT vs AC to Gen Input/DB load
Hi Keith & everyone, I recently replaced a SolarEdge HD 3.6KWp grid tied inverter with the Sunsynk 8kw + 20Kw of LiFe batteries.
It's working fantastically, but - the 11 x 320W JA Panels previously produced 3.6kw with the SolarEdge inverter, due to the SolarEdge PV P370 DC Power Optimizer modules which were added to each panel, making each panel +-25% more efficient! (Ran it that way for 4 years).
Now, having had to take the SE panel optimizer modules off each panel (because they are not compatible with the Sunsynk MPPT; confirmed via testing, panels stay in 1v fire/safe/installer mode) the panel array is only producing 2.5KW :(
So here is my question for the electrical math gurus - should I rather put the SolarEdge inverter back in, with the SE panel optimizers and make 3.6KW of PV and then feed that AC to the Sunsynk to use (Gen input or couple to load/DB board), or is it more efficient to connect the lower output DC array (2.5KW) directly to the Sunsynk MPPT controller? i.e. with respect to battery charging efficiency, is it better to give the Sunsynk MPPT less DC "directly", or "more" (3.6KW) AC at 16-18A?
Thanks!
Billy
Hi Billy, Keith & everyone,
I just add a 5kW sunsynk inverter with 14kWh pylontech battery storage to my 4.8kW SE PV with 4.8kWh Moixa battery system (FIT system).
I have splinted my DB to two. Sunsynk supplied to house. 2nd DB connect to SE, Moixa, Sunsynk and Zappi charger. I use Sunsynk inverter as grid tie inverter without PV.
First week trial, the sunsynk charge and discharge battery perfectly. 0030 - 0430 SOC: 80% Grid. 0430-0030 SOC: 20% But there is no charge from SE. Even Zero export set, none of surplus divert to charge the battery. ( bi-directional inverter!!!)
Second week trial:
0030 - 0430 SOC: 80% Grid
0430 - 0700 SOC: 60%
0700 - 1400 SOC:100% Grid
1400 - 0030 SOC: 20%
Battery charge to 40 amp.
The Sunsynk start charge the battery using SE and Moixa (balance the load without draw from grid) during 0700 - 1400. After 1400, SE will charge the moixa battery until it full then any surplus will export.
I also would like to know Could I connect SE to GEN port and set the system mode from 0700 - 2100 GEN? Will sunsynk charge the battery? Thank you.
Regards,
Yuan