suds7162

Thanks for the insights. My use-case is backup, with a possible solar expansion later on, funds permitting. For now I'm planning on using AGM batteries, as that is what I have. Future upgrades to lithium will be limited then. The unit has specific charging algorithms for Li batteries which is better than some budget inverters. I totally missed the panel wattage recommendation. I'm not sure I understand that though. Surely all I need to do is to ensure that the VOC of the string of panels are within the limits of the MPPT input then all will be well? There are many panels available with significantly more power output, but a VOC of 30-40V which seems to be still within spec. Perhaps this manual is quite old?

I assume you have electricity meters installed on each unit right? And since your complex is modern-ish, I also assume that these meters are digital, and not the old school "spinning disk" style meters. If these assumptions are correct then read on. As far as I understand modern digital power meters do not "spin backwards" like the old school ones do. If you feed power into the grid then they count forward. This means your fancy solar system will cost you double! In addition to that, if your inverter does not know to switch itself off if the outside power is off (proper grid-tied), then you run the risk of electrocuting someone. If the whole complex needs to be switched off for maintenance work, and your system is pumping power into the complex grid, how will the electrician working on something somewhere know that? In general it's Not Advised to do what you are thinking about. In some places it's totally fine to feed power back into the grid, and you are credited the units you feed back. That way you use the national grid as a battery, pumping solar in by day, and pulling it back out again at night. I don't think our little Eskom is equipped to handle that type of complexity.

Hello all, I'm interested in knowing if anyone has experience with the brand "MUST". Specifically, this one for sale at Phase Energy The product seems good and feature rich. I asked them to share with me a data sheet or manual. I attach the document they sent me. The reason why I'm looking at this is because all the Axperts at the same price point is either sold out, or their prices have gone up. Mecers are nowhere to be found in stock, and the RCT branded ones are approaching R10k for the 3KVA models which is nuts! User-Manual-PV18-3-5KW-VHM-off-grid-MPPT (2).pdf

Hello, I want to ask the forum if anyone is familiar with the company BSI Renew and the products that they offer. They seem to be an arm of BSI, who is contracted to do most of the battery related services for our telecoms infrastructure. Think backup batteries at cellphone towers and all that. They sell "refurbished" batteries and a very very competitive price. Alongside that they offer a 1-year warranty on their batteries which makes the entire deal quite attractive. I have actually purchased from them in the past, I have 2x 180Ah Monbat batteries running in my home-office UPS, that can keep my equipment running for 12h+. During a normal loadshedding the battery level rarely dips below 80%. I've had these batteries now for probably 4-5 months and so far, I'm quite happy with their performance. I'm now considering getting more of their batteries and upgrading my office UPS to a whole-home UPS to keep the lights, fridges and so on alive. My question to the forum is if anyone else has experience with their batteries, and maybe some longer term stats for the batteries? How much lifetime can I expect, how many cycles, etc etc. I don't want something that'll last me 12 months then completely drop off a cliff. My use-case for these batteries do not involve daily cycling (loadshedding excluded), as I want to use them for backup, and not to keep the house running when the sun does not shine. For something that'll be fully cycled every day (>50% DoD) I reckon lithium will be the better option, with it's cycle life measured in the 1000s.

Hello all, New user checking in. The current state of Eskom and the stark reality of loadshedding for probably the next (let's be realistic here) decade has finally spurred me on to get something installed that will help us become a bit more independent from Eskom and keep the essentials running in the case of a total grid collapse (something I'm now taking serious as a likely outcome). To keep costs low, I am going to do the installation myself, starting with a battery backup system, then adding on solar and/or a standby generator depending on how impending the level of doom is going to be at that time. I will probably create more posts about this as I go along this journey. I might not remain in this country for very long, depending on some developments at my employer. This means a R100k+ investment tacked on to my bond is out of the question. I want something small for lights and the fridges and now and then the TV, with enough battery capacity for stage 6-8-10, and then add to that a small (2-3kva) generator that's exclusively used to charge the batteries. This to be used only if we have proper extended darkness. Solar can then come after the emergency backup is in place, but that's a bonus. My question for this thread, and the means of my introduction, is to try and find out if anyone can assist in giving me the high-level requirements for a COC. Like I said, my plan is to do the install myself, but then I want to get a COC of the install, to ensure my insurance and all that is happy. I don't want to cut corners with this stuff, and I want to do the wiring/install proper. I'm just not really willing to pay someone R100's per hour, when I am more than capable to do it myself. I know you need some form of DC disconnect/fuse for both the battery bank and the solar (if present), but I'm unsure about the wiring into the existing DB board and this is where I would appreciate some assistance and guidance. I will have a crack at a diagram later today to share with you my thoughts and plans, and then we can see what the hivemind thinks of my plan, and where I need to make changes to remain compliant. Thanks!