May 12, 20233 yr Hi I'm new to the solar experience having had my system installed two and a half weeks ago. The system is working fine and I realise winter will produce a lot less but we haven't had any problems thus far. I have noticed though that the batteries consistently discharges to 60% during the night. Running at night is a tv, av receiver, 2 or 3 LED inside lights for about 5 hours, and then all through the night about 7 outside LED lights (10W), 5 security cameras and the wifi and ONT. Does this seem right that the batteries would discharge that much? Also when I look at graphs, there seems to be power usage spike twic during the night. Is it possible that the geyser was connected to the solar system? the installer told me the geyser and stove were excluded and are grid dependant only. (haven't used the stove in more than a year, it's switched off at the DB board). The system consists off: 8x 455 Mono Percium Solar Panels 1x Deye 5kW Hybrid Inverter 2x Dyness 5.12kWh Block Lithium-ion Batteries The third spike during the day was right after loadshedding ended and I suspect the geyser started heating up after morning showers.
May 12, 20233 yr we need to see how you've setup your time of use settings before we can assist - often there is something there thats causing this. FWIW a constant draw from lights, fridge and other devices can get your batteries down to that level. What level were you hoping to achieve?
May 12, 20233 yr 7 x Outdoor floods are 70W for ~10 hours = 700Wh 5 x cameras are probably another 50-150 (Including the DVR) for ~10 hours = 1.5kWh (worst-case) TV/AV can easily do 250W or even more, for ~5 hours = 1.25 kWh Let's add another 50W worth for inside lights, WIFI, cellphone chargers, bed lights, laptops etc, for ~5 hours = 250Wh This all adds up to 3.7kWh, which is basically 40% of your battery capacity (10kWh total). Some things that you are not considering: Fridges/Freezers The inverter and battery itself requires about 100-200W just to keep their own internal electronics up and running Please post a full 24 hour graph of your battery SOC, and a full 24 hour graph of your inverter load output. Those two early morning spikes are concerning, but too short for a geyser?
May 14, 20233 yr Author Thank you, that does make sense. Here's the SOC graph. The first spike between 09h00 and 09h30 was when we showered. The pool comes on at 10h00 until 15h00. Around 15h00 some washing was done and the microwave was used resulting in the 2nd spike and the last spike at 18h30ish was the microwave again.
May 14, 20233 yr Author On 2023/05/12 at 2:04 PM, mzezman said: we need to see how you've setup your time of use settings before we can assist - often there is something there thats causing this. FWIW a constant draw from lights, fridge and other devices can get your batteries down to that level. What level were you hoping to achieve? Thanks. Here are the times of use (as per the installer, I'm not comfortable enough in my knowledge yet too play around with these)
May 14, 20233 yr Your timer settings basically explain that during the night the battery is allowed to discharge until 60% remains. The other thing to check on the System Work Mode setting is whether you have "Zero Export to CT" checked. That would allow the geyser to to be powered from your battery even though it's on the non-essential loads. Because yes, looking at your 24h cycle, there is a spike of 3kW ag 3am that is most likely a geyser, and yes, it is supported by battery. Maybe if you state in words how you want the system to operate, one could suggest settings that could give you the desired working. Edited May 14, 20233 yr by GreenFields
May 14, 20233 yr You have a spike in consumption at 3:00 in the morning. It doesn't last long, but it takes a big chunk out of SOC. 3.something kW, so that seems like a geyser. But you're at about 55% SOC at 6:00. That's not bad. The battery has got you through the night, and you still have a bit left in case there's an early morning shed and poor weather. So is this so bad? This is similar to what I get with a different inverter but a similar amount of battery. I usually have 60 to 55% SOC remaining about 6:00 in the morning, with the water being heated (heat pump). Since the heat pump is controlled by a timer, and with the outbuildings, including pool pump, not being backed up, I would expect to get some useful backup if the grid went down at 6:00 and PV was poor. Especially if we exercise some discipline and use the gas stove rather than appliances.
May 15, 20233 yr Author 19 hours ago, GreenFields said: Your timer settings basically explain that during the night the battery is allowed to discharge until 60% remains. The other thing to check on the System Work Mode setting is whether you have "Zero Export to CT" checked. That would allow the geyser to to be powered from your battery even though it's on the non-essential loads. Because yes, looking at your 24h cycle, there is a spike of 3kW ag 3am that is most likely a geyser, and yes, it is supported by battery. Maybe if you state in words how you want the system to operate, one could suggest settings that could give you the desired working. Thank you for the info. Zero export to CT is checked. The system works fine, I was just curious about the spikes and the geyser being on the system possibly overloading it. But it seems to work fine as is. When there is loadshedding and we use the shower, the geyser doesn't take from the battery but only switches on when the grid is back online, so it's all good.
May 16, 20233 yr On 2023/05/15 at 8:50 AM, ChristoS said: When there is loadshedding and we use the shower, the geyser doesn't take from the battery but only switches on when the grid is back online, so it's all good. Yes, if the geyser is connected on the input side as a non-essential, then it'll work like this. That early morning geyser spike eats up some battery capacity, but that's because your battery SOC is still above the minimum set on the timer (60%). This is fine, because you probably generated that bit of SOC% with the sun, so it's "free" electricity. A kWh is a kWh after all. What concerns me a little is the PV graph. Why do you have this big notch in the middle of the day? Your battery is not at 100%, yet your solar production goes down? Was this screenshot taken on a day where you had cloudy weather at noon? It's way to smooth for that imo... Edited May 16, 20233 yr by suds7162
May 16, 20233 yr 2 minutes ago, suds7162 said: Yes, if the geyser is connected on the input side as a non-essential, then it'll work like this. That early morning geyser spike eats up some battery capacity, but that's because your battery SOC is still above the minimum set on the timer (60%). This is fine, because you probably generated that bit of SOC% with the sun, so it's "free" electricity. A kWh is a kWh after all. What concerns me a little is the PV graph. Why do you have this big notch in the middle of the day? Your battery is not at 100%, yet your solar production goes down? Was this screenshot taken on a day where you had cloudy weather at noon? It's way to smooth for that imo... shading perhaps ?
May 16, 20233 yr 17 minutes ago, suds7162 said: Yes, if the geyser is connected on the input side as a non-essential, then it'll work like this. That early morning geyser spike eats up some battery capacity, but that's because your battery SOC is still above the minimum set on the timer (60%). This is fine, because you probably generated that bit of SOC% with the sun, so it's "free" electricity. A kWh is a kWh after all. What concerns me a little is the PV graph. Why do you have this big notch in the middle of the day? Your battery is not at 100%, yet your solar production goes down? Was this screenshot taken on a day where you had cloudy weather at noon? It's way to smooth for that imo... I think this is a firmware related bug ,made a thread about it recently.
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