Inverter size
Good morning all, can i ask for a bit of advice please? ATM, solis hybrid 6kw, 2 x fox lv5200 batteries and 12 x 405w panels. I want to upgrade to the 10.5kw hybrid KH. My question is, will there be any problems with putting a 10.5kw inverter onto less than 5kw worth of panels? I have room on my roof to double that, just about, but it won't happen yet awhile. The inverter will be wired to power the whole house, with the backup output going straight into my fuse box. (Obviously through a few other things first). This is how it is wired ATM and works great. Except when we exceed the kw output of the solis and it shuts down. This is why we want to increase the output kw, so my partner does not have to worry about what else is running in the house when she wants to switch the kettle on! She cant get to grips with solar and kw ratings, amperage etc and she will not be able to learn it. So i am trying to make it as foolproof as possible for her. Thanks.
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Dave Foster
- Posts: 1328
- Joined: Thu Oct 13, 2022 7:21 pm
The KH10.5 supports up to 4 separate PV strings, so there is plenty of scope to expand later - the main thing is to ensure you don't have too few panels on 1 string (minimum
4, ideally 5), and also not to exceed a single strings maximum current - in the case of the KH they specify a max power of 3,300 watts.
So the ideal configuration would be to have your existing 12 panels in 2 strings of 6 panels which has a max power of 2,430 and well within the string maximum.
You can't use the LV5200's on the KH so you would need to choose a different battery stack - you have a few options there is the HV series (max up to 20.4kWh) the ECS series (max up to 43.2kWh), the EP5 series (max up to 20.72 kWh) and soon to be EP11 series (max up to 41.44kWh).
In effect the EP series in looks is similar to the LV's in looks, the ECS batteries are a very stylish design and the HV batteries are more akin to a rack mounted battery system.
But you need to consider the ability for the KH system to provide the full 10.5kWh output when running totally on batteries, all Fox batteries have a recommended discharge current and so to meet the max power you need the voltage to be high enough to allow max power safely - you need to ensure your battery choice works for that (for example you would need 2 * EP5 batteries or 8 * HV2600 batteries or ECS4100 * 5 ) - certainly the EP5 are the best 'bang for the buck'.
4, ideally 5), and also not to exceed a single strings maximum current - in the case of the KH they specify a max power of 3,300 watts.
So the ideal configuration would be to have your existing 12 panels in 2 strings of 6 panels which has a max power of 2,430 and well within the string maximum.
You can't use the LV5200's on the KH so you would need to choose a different battery stack - you have a few options there is the HV series (max up to 20.4kWh) the ECS series (max up to 43.2kWh), the EP5 series (max up to 20.72 kWh) and soon to be EP11 series (max up to 41.44kWh).
In effect the EP series in looks is similar to the LV's in looks, the ECS batteries are a very stylish design and the HV batteries are more akin to a rack mounted battery system.
But you need to consider the ability for the KH system to provide the full 10.5kWh output when running totally on batteries, all Fox batteries have a recommended discharge current and so to meet the max power you need the voltage to be high enough to allow max power safely - you need to ensure your battery choice works for that (for example you would need 2 * EP5 batteries or 8 * HV2600 batteries or ECS4100 * 5 ) - certainly the EP5 are the best 'bang for the buck'.
Good morning Dave, thank you for the info. So, depressingly, i cant use my batteries with the 10.5. Buying a whole new system at the moment just isn't happening. Back to the original plan then, which is a sunsynk 8kw. I know the lv5200s work well with sunsynk, according to people who have this setup on the sunsynk forum.