February 22, 201610 yr 12 hours ago, The Terrible Triplett said: Guys / gals, shoot me if you feel the need but I think this needs to be said. It never hurts to hear it again :-) 12 hours ago, The Terrible Triplett said: Take as an example, the following load: Full size Energy Star Rated refrigerator: 400kWH per year / 365 days per year = 1.1kWH = 1100WH per day Amateur! :-P Mine uses a mere 112kwh a year. Bosch KSV36VL30. It's not even all that expensive and it is a really really nice fridge. Sometimes I wonder what is wrong with people... buying the wrong appliances and stuff... :-) 12 hours ago, The Terrible Triplett said: Say you want 2 days of energy storage and 50% maximum battery discharge: 3800WH per day x 1/0.85 AC inverter eff x 1/24 volt battery bank x 2 days storage x 1/0.50 max discharge = 745 AH @ 24 volt battery bank If you use golf cart batteries (6 volts @ 200 AH per battery) you need 4 x parallel strings of 4 batteries per string = 800 AH @ 24 volt battery bank. I think that here in South Africa where we do have a somewhat stable grid, and where we have more sunshine than in Europe, it's perfectly okay to do just one day of storage with 50% DoD, if you cannot afford the large bank, and it's actually not that hard to get enough storage for a day. You could do it with a 24V bank made up of 4 x Trojan T105RE batteries. Remember that half the time the load runs while the sun is shining... :-) Of course you need proper management hardware, which is why you want jdp's software, a Victron BMV... or my upcoming open source project if and/or when that's ever finished :-)
February 22, 201610 yr 11 minutes ago, The Terrible Triplett said: Understand this, correct me if I am wrong, but if you use a Voltronic device as a UPS it will, with enough Eskom failures, destroy any battery bank. I've had that conversation with people, on Facebook mostly, and people got very upset with me because I'm trashing the product they are trying to sell. When the first ones started hitting the market in my home town, in the midsts of load shedding, I pointed out how the maximum open circuit voltage was just pathetic (I think this was on the lower end 24V models) and it basically meant that you'd be placing all your panels in parallel. I also pointed out the low maximum voltage (I think it's 30V on the 24V models) which means you cannot properly equalise half the batteries out there. Third, I learned about the voltage based SoC issue, which means it is okay if you have one power failure a week and you can float-charge your batteries to 100% over the other 6 days... but with regular load shedding (and the crap batteries people were bundling) it was a sure thing that within 2 years people will by buying new batteries. Now at least this inverter is a giant leap (not just a step) up from the MSW crap other providers were selling. Which led me to the conclusion that the Axpert/Must/RCT inverter is really good value for money, but only because it costs so little money :-) As always though... watch this space. I think these Chinese boikies are learning... :-)
February 22, 201610 yr 3 hours ago, The Terrible Triplett said: You can only stop that 2 ways: 1) Get the battery bank and load specced to the T - very expensive.. 2) Or you you stop the inverter, under load, at say 50% battery SOC. You cannot use volts for that, you have to use the battery SOC for that. That's why we add the BMV and some smart software. Fixes the biggest flaw they have, Still only makes it 13-14k
February 22, 201610 yr Viper_ZA ... I laughed lekker!!! But I wonder, out of interest, a) how many users of Axpert know this in SA and b ) how many of them have installed the software you mention with a BMV and c) will be happy with the increased power consumption for adding a PC/Laptop (their is no Rpi version yet) to accommodate Voltronic's oversight. For until everyone knows the danger, like Plonkster said, a lot of batts are going to be replaced in the next few years.
February 22, 201610 yr Okay, I forgot the cost of my tablet for keeping increased power consumption low
February 22, 201610 yr Ja, that +-10watts of my tablet annoyed me endlessly, so therein the Rpi idea. So you have a 25w load when the Axpert is just sitting there, with the tablet watts on top of that?
February 22, 201610 yr 20 hours ago, The Terrible Triplett said: DJacobs, may I ask, why on earth did you take 12 x 105ah leisure batteries? This is how you get caught, not knowing, Led Solar World in centurion.
February 22, 201610 yr 1 hour ago, The Terrible Triplett said: Ja, that +-10watts of my tablet annoyed me endlessly, so therein the Rpi idea. So you have a 25w load when the Axpert is just sitting there, with the tablet watts on top of that? Yeah +- 10watts when on solar during the day I can live with. (Charger 5v @ 2000ma) I'll pull the charger at night can run this thing on 6000mah batt for some time Or just turn off a light or two
February 22, 201610 yr 32 minutes ago, viper_za said: Yeah +- 10watts when on solar during the day I can live with. (Charger 5v @ 2000ma) I'll pull the charger at night can run this thing on 6000mah batt for some time Or just turn off a light or two Same here. 10w or 1000w on solar, does not matter. Go big, go wild. But if you are like me, running lean and mean, every watt counts at night for I want my 10 years from the batts and I want to recharge them as early as possible for that generates the most savings. And off course you are not forgetting that not everyone is going to take their tablet and connect it permanently to the system like you, They are not that cheap, an additional cost on top of the Axperts costs (?). Chances are it is going to be an old laptop / Pc that was not necessarily on 24/7, which is adding a lotta AH used when running off them batts. And if the laptop/Pc is running of Eskom, you are sacrificing some of the savings you make daytime. Viper ... it was fun.
February 22, 201610 yr Hi Guys, I am lost with all these calculations. I am not as qualified and only dependant what was installed, but my gut tells me the settings are wrong. Please assist. 01 Sol 02 60A 03 apl 04 sds 05 use 06 lte 07 lte 09 50hz 11 30amp 12 46V 13 54V 16 cso 18 bon 19 tep 20 lon 22 aon 23 byd 25 fds 26 58.4V 27 52.8V 28 sig 29 42V 30 one 31 41V I have 12 x 250w panels, 12 x 105amp/h dixons, 1 x 5kw axpert. There 4 x batteries connected together. Please guys, help a man inneed. 0827600417 Daniel
February 22, 201610 yr 28 minutes ago, The Terrible Triplett said: Viper ... it was fun. Touché TTT PS my night time load with ceiling fan also running + outside lights + fridge + chest freezer. This was my avg watts for 5 hours last night (think my batts should last )
February 22, 201610 yr Daniel, those are good batts for starters. Just keep the water levels checked. Dixon gives free water if you need, and they are very helpful. How are the batts connected to the inverter? Dixon - DC 105 DT Data Sheet.pdf
February 22, 201610 yr Here is the data sheet for the Dixon 105ah. If you keep them at 20% DOD, you could get 1000 cycles, which is very good. Dixon - DC 105 DT.pdf
February 22, 201610 yr Specs for the batts The Max the Axpert can do is 58.4V. Will go through your settings now
February 22, 201610 yr 4 x Batteries are connected together and then linked. So it seems like 48v x 3 if it sounds right.
February 22, 201610 yr That we will show you once Viper have sorted your settings. And Chris Hobson and others can advise on balancing the batteries, as he has found a very neat way of doing it. But where the inverter is connected to the batteries, is very important.
February 22, 201610 yr As the batteries are packed next to each other, the positive (red) is connected at the end of the bank and the blue on the first bank on the other side.
February 22, 201610 yr You can, or hold on, I am looking for the right diagram. How did the connectors? I would remove the insulation tape.
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