December 23, 20169 yr Author Hi Chris. The other thing to consider, the electricity department hates these systems. If your PV modules are visible you can expect a visit from them. If your system is going to be a stand-alone off-grid setup then you should have minimal hassle. My setup still has an old analogue meter that's located inside my property, the Authotities are now forcing me to change to a prepaid meter. I'm being harassed and forced to do things that benefit them and not me. They are treating me like a criminal. Funny thing is, if you read the papers it looks like they are encouraging solar and energy efficient systems, don't be fooled, they only encourage it if it belongs to them. I'm now looking at adding a few more panels, getting a massive lithium bank and going off grid completely. If you or anybody ever have hassles like this you need to let an energy manager like Ikapa Power Management handle the situation, they know all the laws and have the ability to audit your account and rectify any over billing etc, don't allow anyone to bully you. Sent from my iPhone using Tapatalk
January 28, 20179 yr Author Rearranged my 2 strings to illuminate partial shadowing Sent from my iPhone using Tapatalk
January 28, 20179 yr Author This was at 17:00 with 2 more hours of sun. Sent from my iPhone using Tapatalk
February 8, 20179 yr Author Hey guys. So I finally got some battery power to match, it's going well, been off-grid for a week now. We have 16 x 200Ah Gel Vrla Agm, 4 strings. Sent from my iPhone using Tapatalk
February 8, 20179 yr 59 minutes ago, Neb said: Hey guys. So I finally got some battery power to match, it's going well, been off-grid for a week now. We have 16 x 200Ah Gel Vrla Agm, 4 strings. Where are the busbars and equal lengths of cable between the batteries and the busbars and where are the string fuses? I guess those batteries were not cheap, so you would want to do everything possible to protect your investment.
February 8, 20179 yr Author All relevant cables are the same length, fuses are on the wall next to Imeon, I'm just waiting for the battery balancers.No busbar used here Sent from my iPhone using Tapatalk
February 8, 20179 yr 21 minutes ago, Neb said: All relevant cables are the same length, fuses are on the wall next to Imeon, I'm just waiting for the battery balancers. No busbar used here This was discussed many times here on the forum. If you have parallel battery strings you need to ensure that the cable lengths in each string is of the same length and type in order to use (discharge) and charge each string equally. The easiest method is to add busbars and the have equal length cables between the batteries and the busbars. You already have equal lengths and types of interlink cables between the batteries in each string, but the ends of the strings are not connected optimally and therefor the strings will not be utilized equally. Another must have, besides the fuse / breaker between the battery bank and the inverter is a fuse per string - also discussed a few times on the forum. If everything is connected as described above, you can get away with only 1 x HA-02 battery balancer.
February 8, 20179 yr 4 hours ago, superdiy said: This was discussed many times here on the forum. If you have parallel battery strings you need to ensure that the cable lengths in each string is of the same length and type in order to use (discharge) and charge each string equally. The easiest method is to add busbars and the have equal length cables between the batteries and the busbars. You already have equal lengths and types of interlink cables between the batteries in each string, but the ends of the strings are not connected optimally and therefor the strings will not be utilized equally. Another must have, besides the fuse / breaker between the battery bank and the inverter is a fuse per string - also discussed a few times on the forum. If everything is connected as described above, you can get away with only 1 x HA-02 battery balancer. Agreed. Those batteries will be charged un-balanced. The ones closest to the inverter will work hardest while other two banks will be under charged.
February 8, 20179 yr Author Agreed. Those batteries will be charged un-balanced. The ones closest to the inverter will work hardest while other two banks will be under charged. Sent from my iPhone using Tapatalk
February 8, 20179 yr Hi Neb I love your system and especially the grey beast you putting so well on show here !!!! Regrettably, I have to agree with Silvernodashi and Superdiy ( The SS twins ....lol!! ) regarding your cabling. It is a recipe to destroy your investment. Remove the cables from pos. and neg. mains of each string and replace with four sets of black & red, all exactly the same length. ( The length of the longest cable required) Put 2 busbars on the wall underneath your existing fuses and fit all the neg & pos. cables to the busbars . You've already got 2 fuses, just add another 2 and put them on your neg. / or pos. cables just before the busbar. From the busbar 2 cables to your Imeon. If you want to you could add a 200amp DC circuit braker between your busbars and the imeon for security. Cables sorted and it would be definitely much cheaper than replacing the batteries in a year's time. You could use one HA-02 like the twins has suggested, would work perfectly, but a lot of wiring. I opted for 4 x HA-02 equalisers, one for each string and within days my bank was just about 100% balanced. With an investment like yours, I would definitely invest in a BMV 702 and have peace of mind forever. Don't take me on Superdiy, you know I'm scared of you !! Cheers
February 9, 20179 yr The fuses on the cross links between the strings can be automotive blade type fuses correct?
February 9, 20179 yr 1 hour ago, DeepBass9 said: The fuses on the cross links between the strings can be automotive blade type fuses correct? Yes, either use automotive blade type or inline fuse holders.
February 9, 20179 yr 8 hours ago, Chris-R said: Don't take me on Superdiy, you know I'm scared of you !! What's that supposed to mean?
February 9, 20179 yr 21 hours ago, superdiy said: Where are the string fuses? Neb. On top of the Merson DC Disconnect I use these fuses on each of my strings before the busbar. Personally I would mount the busbars above the bank below the DBboards. You can then make each string connection as short as possible. Top same length as bottom though. You can then run really thick cable between the BusBars and the Merson. I have a separate HA02 for each string. Initially I also had one across 2 strings but I have found that they perform better with an HA02 per string. Less wires and fuses as well AND the HA02 are only rated @ max 10A so given your loads and inverter one will not be enough for 2x strings. (I believe).
February 9, 20179 yr Author Here's a diagram to show the resistance at each battery string, shown as a circuit with values for cable resistance as R1 and R2, I'm only using 2 different length cables. The total resistance for each string is R5 I agree that I need balancers and fuses but I'm struggling to understand why I would need busbar and equal length cable when the resistance in my circuit is all the same for each string? Sent from my iPhone using Tapatalk
February 10, 20179 yr Hi Neb. Measure the resistance of the cable and exclude the batteries. In order to balance the batteries you need to get the string(cable) resistance as equal as possible. Lets me also say. The system is the envy of many here including myself. Maybe why we are all keen for it to be as perfect as it looks My 2c anyway.
February 10, 20179 yr 11 hours ago, Neb said: Here's a diagram to show the resistance at each battery string, shown as a circuit with values for cable resistance as R1 and R2, I'm only using 2 different length cables. The total resistance for each string is R5 I agree that I need balancers and fuses but I'm struggling to understand why I would need busbar and equal length cable when the resistance in my circuit is all the same for each string? Sent from my iPhone using Tapatalk Can you please write down the exact resistance values for each of those points, and show us?
February 10, 20179 yr Author Can you please write down the exact resistance values for each of those points, and show us? Yeah, will try do that. But so far it makes sense or not? You can replace R1 and R2 with whatever value you want, the result will still be equal resistance for each string? Unless of course I could be wrong. Sent from my iPhone using Tapatalk would a battery balancer deal with the slight variation in equal length cable (I'm sure there's always a slight variation when crimping lugs onto equal length cable?)
February 10, 20179 yr Author Hi Neb. Measure the resistance of the cable and exclude the batteries. In order to balance the batteries you need to get the string(cable) resistance as equal as possible. Lets me also say. The system is the envy of many here including myself. Maybe why we are all keen for it to be as perfect as it looks My 2c anyway. Thanks Mark. Sent from my iPhone using Tapatalk
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