jcdesenhaf
New Member
- Joined
- Aug 28, 2021
- Messages
- 7
IT seems that sharing the DC output of two panels (in parallel) confuses one of the two panel-mounted microinverters when grid tied.
Solution ideas?
Here's the scene:
I own an 11 panel grid-tied system Sunpower X21-345 with SOLARBRIDGE (Enphase) Type E microinverters under each panel. The microinverters are daisy-chained delivering 240 to the panel and safely switch off when there's no load (power out situation)
With rolling blackouts being common here, I've successfully tapped one panel's DC line through a Y-fitting to charge two 200AH Renogy batteries through a Victron SmartSolar MPPT 50 Amp Charge Controller. The DC line is fused, switchable, 6AGW, and safely routed. Add a 3KW 24v sine inverter, and it works great to run the fridge, computers, internet, whatever on a completely independent circuit when the power's out. Easy.
Then, I got greedy.
I connected a second panel's DC line, in parallel, to my DC feed up at the panels. In testing, It worked great, delivering 500 watts at 10 amps while also delivering power to the grid.
Nice, huh? Only when the power is out though.
It seems that connecting two panels' DC lines in parallel confuses (reduces output of) one of the microinverters when grid-connected. This is with no other DC load (my charge controller is disconnected). It takes about 10 minutes for it to happen, but it is consistent.
How do I know this? Well, I just finished setting up network access to my Sunpower PVS6 system and am capturing the stats for each of the inverters for the last few days.
When I have two panels sharing the same DC line (in parallel), one of the two microinverters involved drops its amps down to about 22% of its normal output. This is with my charge controller and any DC load disconnected.
Any ideas of ways around this? Or am I destined to run a second pair of 6AWG through the house, or climb the roof to connect the second panel for every power outage?
All ideas appreciated.
Solution ideas?
Here's the scene:
I own an 11 panel grid-tied system Sunpower X21-345 with SOLARBRIDGE (Enphase) Type E microinverters under each panel. The microinverters are daisy-chained delivering 240 to the panel and safely switch off when there's no load (power out situation)
With rolling blackouts being common here, I've successfully tapped one panel's DC line through a Y-fitting to charge two 200AH Renogy batteries through a Victron SmartSolar MPPT 50 Amp Charge Controller. The DC line is fused, switchable, 6AGW, and safely routed. Add a 3KW 24v sine inverter, and it works great to run the fridge, computers, internet, whatever on a completely independent circuit when the power's out. Easy.
Then, I got greedy.
I connected a second panel's DC line, in parallel, to my DC feed up at the panels. In testing, It worked great, delivering 500 watts at 10 amps while also delivering power to the grid.
Nice, huh? Only when the power is out though.
It seems that connecting two panels' DC lines in parallel confuses (reduces output of) one of the microinverters when grid-connected. This is with no other DC load (my charge controller is disconnected). It takes about 10 minutes for it to happen, but it is consistent.
How do I know this? Well, I just finished setting up network access to my Sunpower PVS6 system and am capturing the stats for each of the inverters for the last few days.
When I have two panels sharing the same DC line (in parallel), one of the two microinverters involved drops its amps down to about 22% of its normal output. This is with my charge controller and any DC load disconnected.
Any ideas of ways around this? Or am I destined to run a second pair of 6AWG through the house, or climb the roof to connect the second panel for every power outage?
All ideas appreciated.