My current setup:
2 * 250 Watt Panels in SERIES, (Panel Specs:- Voc: 37.3, Vmp: 30.1, Isc: 8.78, Imp: 8.31)
These 2 panels feed a Victron SMART controller 150/35 which then feed a
DIY (LiFePO4) 4 * 3.2v prismatic cells (12.8v NOMINAL), with 4sDALY BMS.
Now I've used a calculator on the Victron site and it only recommended 2 PANELS for my controller, charging a 12v battery.
Now I understand to ADD the VOC for the panels and ensure < than 150v. I also understand that the controller will MAX output 35Amps to the battery.
With this in mind I ask the following questions (I apologise in advance, this is my very first system & I'm still learning and trying NOT to make errors that may be dangerous or costly)
1) If my battery is 100% SOC, where does the excess energy from the panels go? Is it dissipated as heat via the fins on the back of the Victron controller? Does the controller simply stop pulling energy from the panels (is that such a thing? I watched a Youtube video that said this WAS the case) Do the panels remain in a high charge state and thus start to degrade and is this dangerous/damaging?
2) I'm in the Southern Hemisphere and Spring has just begun, so my 2 panels rarely produce their maximum energy CONSISTENTLY. With this in mind, can I ignore the Victron sites calculator, and just add more panels, providing I remain < 150v? For instance 4 series panels (250 Watt Voc 37.3) = 149.2v which is < 150. Is that TOO close? Or would I be better doing 2S2P config? I realise my controller will MAX at 35A, however I would like the system to be able to be at MAX for longer throughout the day using greater solar collection. Is this safe to do, even if the battery reaches 100%SOC early in the day?
(P.S. This system is on an off grid shed, powering a beer fridge (24*7), lights and a TV, but may be used for tools if I can get more power. F.Y.I. I have ordered 2 more Victron 150/35) and have 10 additional panels at my disposal. Also considering building a 48v 310Ahr prismatic cell battery)
2 * 250 Watt Panels in SERIES, (Panel Specs:- Voc: 37.3, Vmp: 30.1, Isc: 8.78, Imp: 8.31)
These 2 panels feed a Victron SMART controller 150/35 which then feed a
DIY (LiFePO4) 4 * 3.2v prismatic cells (12.8v NOMINAL), with 4sDALY BMS.
Now I've used a calculator on the Victron site and it only recommended 2 PANELS for my controller, charging a 12v battery.
Now I understand to ADD the VOC for the panels and ensure < than 150v. I also understand that the controller will MAX output 35Amps to the battery.
With this in mind I ask the following questions (I apologise in advance, this is my very first system & I'm still learning and trying NOT to make errors that may be dangerous or costly)
1) If my battery is 100% SOC, where does the excess energy from the panels go? Is it dissipated as heat via the fins on the back of the Victron controller? Does the controller simply stop pulling energy from the panels (is that such a thing? I watched a Youtube video that said this WAS the case) Do the panels remain in a high charge state and thus start to degrade and is this dangerous/damaging?
2) I'm in the Southern Hemisphere and Spring has just begun, so my 2 panels rarely produce their maximum energy CONSISTENTLY. With this in mind, can I ignore the Victron sites calculator, and just add more panels, providing I remain < 150v? For instance 4 series panels (250 Watt Voc 37.3) = 149.2v which is < 150. Is that TOO close? Or would I be better doing 2S2P config? I realise my controller will MAX at 35A, however I would like the system to be able to be at MAX for longer throughout the day using greater solar collection. Is this safe to do, even if the battery reaches 100%SOC early in the day?
(P.S. This system is on an off grid shed, powering a beer fridge (24*7), lights and a TV, but may be used for tools if I can get more power. F.Y.I. I have ordered 2 more Victron 150/35) and have 10 additional panels at my disposal. Also considering building a 48v 310Ahr prismatic cell battery)
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