Solar pv batteries distance to CU

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revor

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On a ground mounted solar pv array supplying a hybrid inverter and batteries housed in a suitable weather proof structure ,  is there a limit on the distance from the batteries to the consumer unit. (It is assumed that the supply cable between the batteries an CU is suitably rated)

 
Panels, hybrid inverter, (does panel DC to AC and also AC to DC to charge batteries from grid) batteries, consumer unit. 

 
your problem will be getting a communication cable to your meter tails, you need an amp clamp or bi-directional meter in the house which needs to talk to the battery charger - I've never seen limit on cable length, but the longest off the shelf cable I know of is 10m. In this scenario you would probably be better off with AC battery pack in the house away from the solar array. Batteries also don't like to get cold, so winter in an outdoor box would not be good for them.

 
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Thanks for that. The plan by the installer was for 2 cat 5e cables think I now understand what these are for one will be as you suggest the other I guess the other for monitoring the system and link to the cloud (I think.)  The reason for my question was that I was looking for an alternative to the Sola X batteries and inverter system that has been proposed as it all made in China and from recent and previous situations no longer think I want my money going there. I reckon I will not be alone in that thinking but time will tell. Whilst browsing possible alternatives came across Powervault and in that spec the distance to the CU is limited to 25 M. I was wondering whether that was a typical scenario in this situation for the different makes. The batteries are limited to temperature variations as you state, I think the spec on the  proposed is 0 to 35 deg outside this range will shut down. I have built a special insulated (not quite finished) small building to house the gear. My initial concern was of possible condensation on the electronics and I would have a little heater in there if needed.  I did something similar but on a smaller scale when some 30 or more years ago installed electric operated gates the control cabinet was outside and I installed a thermostat and little heater in it to avoid condensation and that worked very well. 

 
there are plenty of alternatives to Chinese gear, SMA / LG battery is a good combination, if a little pricey. Whatever you do buy, it's best to buy as a paackage, not all battery controllers are compatible with every battery. This does tend to make buying a pain in the neck! You could of course run long DC cables into the house. This can be achieved with standard SWA cable (ie armoured) rather than armoured solar cable which is very expensive - people forget standard cable has AC and DC ratings.  Don't try to bury solar cable, it doesn't like permanent contact with water, although it could be installed in a duct provided the duct can be kept moisture free. This would mean a single inverter/ battery charge controller in the house. Many installers aren't keen on long DC runs, but seeing as some of the solar frams I've worked on have DC runs in the order of 2/300m it's not an issue, just up cable size to suite. 

 
Thanks Binky, Will have a look at the SMA / LG offerings. I concluded a while ago after consulting this forum that DC underground was not a good idea particularly when I saw one installation where the installer had used SY cable underground to carry DC.  As have built an insulated weather proof housing next to proposed array need to stick to all the gear  being in there also don't have enough room in the house anyway. Looking at what Zhyphen can offer at moment.  Seems though that most battery packs have components made in China. I also want something my installer will be happy with as want him to do the job as being very local and being in a rural area important to put the business his way as his lads are also local. Has also been very helpful when I have had queries.

 
I've fitted a few sets of Pylon and 1 set of BYD batteries - Chinese but seem fine. The charge controller is more critical than the battery I think. BYD make most of the worlds car batteries, the electric bus Boris stood in ront of a little while ago was BYD powered. Fronius do a charge unit that works with BYD. 

 
Thanks binky, how many do a hybrid inverter that does both  DC to AC  and then AC to DC for charging batteries from grid rather than have to have an inverter and a charger. 

I've joined up with Octopus so hoping when I get smart meter will be able to make use of low cost electricity at night to top up and maybe eventually charge a small EV.

 
HYbrid id definetlu the better option, I don't think SMA do one, but check out Fronius,  Solaredge, KACO and apparently LG do a unit although - never seen one of their inverters.

 
Thanks binky.

Came across a UK company based in NI called Zhyphen who design and build bespoke units housed in a rack system which makes it a very flexible system. They use components from different sources and "pick the best".The only snag from my point of view the batteries are Pylon. But if the other components are non China and put together in the UK then it helps to keep more of the spend here. Still trawling through the other suggestions. The proposed system will be more expensive than the Sola x but I am prepared to put my money where my mouth is provided it is not silly. I want to keep the job with the local installer so need stuff that does not need a solar installer "tied" to the equipment. Zhyphen ticks that box. Anyone any knowledge or used them.

 
seen the adverts, but I know no more than that about Zhyphen. Nothing wrong with Pylon batteries, I've fitted a few sets of those. Have a look at Victron stuff, Indian but very good.

 
Got Zhyphen on back burner at moment it is a good set up. Have come up with another option via Aceon a UK battery specialist. An Italian inverter from Delios and BMZ battery packs from Germany with cells made in Korea. Waiting for pricing at moment.

 
Only just seen your posting did not see reply notification. Only just got quote anyway. 3.9K for bat 10KW and 2.3k  for inverter 6.kva. They are set up as a package. Bit pricy though compared to China stuff. Relationships are heating up with them worldwide could get messy I guess over next few weeks. If you are interested in the gear could post link to the brochures. Can only go so far in understanding the specifications have asked my proposed installer to take a look. Started looking for panels now bit more choice.

 
battery price is compatible with the likes of LG,  inverter seems a bit dear. 

Post the brochures, always worth a read. The Solar wholesalers have stream-lined stock levels over the last few years, so the range of products is much reduced and I don't 'see' many options these days. 

 
the inverter certainly looks like  abig unit, that doen't necessarily mean it has reliable components inside, but anythng electrical works better if kept cool, so a bigger box generally means more cooling space for components. What I am less keen on is the fact it has a cooling fan similar to what your comouter has. THe inverter manufacturers I am familiar with have designed these out - check it occasionally for fluff or other debris like spider webs. 

 
I understand your concern re fan but I see it as an advantage in that it will help to minimise chance of condensation the scourge of anything electronic. I have built a small insulated shed to house the equipment which should help and I will put in some sensors to monitor the conditions inside. What I have not worked out yet is how much ventilation to include it will depend on how much heat is generated by the gear. if my installer happy will probably go with this setup. just need to decide on the panels. What is the situation re MCS on solar seems that panels need the certification but the inverters and batteries are not yet included in the scheme?

 
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