Apologies if this is a really basic question as I haven't managed to find the answer elsewhere.
My system was installed 2 weeks ago and yesterday I had an 'error code 64 - DC Bus high' in the afternoon.
Can anyone explain what this means please? What do I need to do about it? System is working normally. Do I need to panic???
Thanks
Error code 64
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Dave Foster
- Posts: 824
- Joined: Thu Oct 13, 2022 7:21 pm
I wouldn’t panic, it will recover from the error but i’d suggest you contact your installer and tell them.
It tends to happen when you have a large number of panels on a solar string when they are under full sun (around midday), if the power exceeds the string limits the inverter will cut the solar generation until the power drops again - ironically it happens more at this time of year because the sun is so strong but the ambient temperature is low, the panels derate as they get warmer in summer.
It’s frustrating as you lose a bit of solar generation but it does no harm - your installer should be able to re-configure your strings to avoid this.
It tends to happen when you have a large number of panels on a solar string when they are under full sun (around midday), if the power exceeds the string limits the inverter will cut the solar generation until the power drops again - ironically it happens more at this time of year because the sun is so strong but the ambient temperature is low, the panels derate as they get warmer in summer.
It’s frustrating as you lose a bit of solar generation but it does no harm - your installer should be able to re-configure your strings to avoid this.
Hello.
I wonder if someone would be able to give some advice please.
I have been getting these same error messages. “Error code 64 DC Bus volt is high”. Wondering if ok.
Apologies if I do not have the right terminology.
I had installed on Weds (scaffold is still up)
16x Longi 430W Panels 6.8kW system size.
Fox H1 5.0-E inverter
Fox mira HV25 batteries with total capacity of 7,370wh
(It was originally due to be 405W or 415W panels but I was told I was being provided 430W panels at no extra cost because i had a delay on my order)
I have had this error code show four times on two different days. Usually around the middle of the day when it is bright outside. All normal apart from this.
According to FoxCloud2.0
Days since commissioning
Day one: 17.6kWh solar produced no errors logged.
Day two: 22.5kWh solar produced. Four error code 64 middle of the day
Day three: 22.8kWh solar produced no errors logged.
Day four (today up to 4pm): 24.2kWh solar produced. Four error code 64 around middle of the day.
I noticed the inverter PV1 310.9v and PV2 310.5v around the time of the latest error log entry.
Is this clipping? (Something I saw mentioned when trying to search online for info).
It did last time switch to 0w solar production briefly so seemed to be akin to a reset rather than throttling back. But not sure.
Should I be worried at all?
I appreciate max PV peak will not be hit all day everyday. (Though we are April so not sure what happens in the summer).
Does this cause any problems for the inverter or warranty?
I am hoping the system has been designed within tolerances.
I read that greater solar production earlier in the day and later in the day more than offsets any clipping in the middle of the day.
Just a bit cautious as I understand that inverters are not a cheap component within a solar setup.
Thank you for sharing any thoughts.
I wonder if someone would be able to give some advice please.
I have been getting these same error messages. “Error code 64 DC Bus volt is high”. Wondering if ok.
Apologies if I do not have the right terminology.
I had installed on Weds (scaffold is still up)
16x Longi 430W Panels 6.8kW system size.
Fox H1 5.0-E inverter
Fox mira HV25 batteries with total capacity of 7,370wh
(It was originally due to be 405W or 415W panels but I was told I was being provided 430W panels at no extra cost because i had a delay on my order)
I have had this error code show four times on two different days. Usually around the middle of the day when it is bright outside. All normal apart from this.
According to FoxCloud2.0
Days since commissioning
Day one: 17.6kWh solar produced no errors logged.
Day two: 22.5kWh solar produced. Four error code 64 middle of the day
Day three: 22.8kWh solar produced no errors logged.
Day four (today up to 4pm): 24.2kWh solar produced. Four error code 64 around middle of the day.
I noticed the inverter PV1 310.9v and PV2 310.5v around the time of the latest error log entry.
Is this clipping? (Something I saw mentioned when trying to search online for info).
It did last time switch to 0w solar production briefly so seemed to be akin to a reset rather than throttling back. But not sure.
Should I be worried at all?
I appreciate max PV peak will not be hit all day everyday. (Though we are April so not sure what happens in the summer).
Does this cause any problems for the inverter or warranty?
I am hoping the system has been designed within tolerances.
I read that greater solar production earlier in the day and later in the day more than offsets any clipping in the middle of the day.
Just a bit cautious as I understand that inverters are not a cheap component within a solar setup.
Thank you for sharing any thoughts.
-
Dave Foster
- Posts: 824
- Joined: Thu Oct 13, 2022 7:21 pm
From what you have said and your string voltages, it sounds like you have 2 strings with 8 panels on each string.
Just to go slightly into technical territory to explain it, you have 8 Longi 430W panels which can output 430W at 33.16V (that is their maximum power point voltage), they are in series so the voltage will be multiplied by 8.
So to do the maths 8 * 430W = 3,440W and the voltage they will be providing that at is (33.16V * 8) = 265.28V, the current flowing will be ( A = W/V ) which is 12.97A and the maximum current the FoxESS inverter will allow is 13.5A peak (so in theory you are in limits).
The voltage of 310V you are seeing is the panels open circuit voltage (39.43V) which is what happens when the inverter powers off the string (it goes open circuit)
Whilst their maximum current is just below the inverters maximum limit, the problem occurs because the panels are rated at 430W at 25C with 1000M3 of solar irradiance - they actually reduce in power as the temperature increases, but equally they are slightly more powerful as the temperature falls and so on a summers day they won't get much past their maximum power, but on a cold day at this time of year their power is just a little bit too high.
What that means is that panels produce more than the 13.5A limit the inverter has, and so the inverter will raise an alarm and shut the string down, as soon as the inverter works out that the power has fallen below it's maximum limit it will turn the string back on again, which is what you are seeing.
Whilst it sounds the same as clipping, it is a different thing - with clipping your panels are generating more power than the inverter is allowed to output (as you have an H1 5.0, your max power is 5 kW) so if you exceed 5kW the inverter will reduce the power point so that it maintains it's maximum power. What you are seeing is it exceed the maximum string current which results in an alarm and it turning off the string temporarily until it can safely turn it back on.
Ironically had the lower powered panels been installed you probably wouldn't have seen this problem.
So a couple of things to run through -
I would definitely mention it to your installer, they need to know and there maybe something they can do to limit it - but for the reasons I mentioned i'm hoping that the problem will remove itself naturally over time.
Just to go slightly into technical territory to explain it, you have 8 Longi 430W panels which can output 430W at 33.16V (that is their maximum power point voltage), they are in series so the voltage will be multiplied by 8.
So to do the maths 8 * 430W = 3,440W and the voltage they will be providing that at is (33.16V * 8) = 265.28V, the current flowing will be ( A = W/V ) which is 12.97A and the maximum current the FoxESS inverter will allow is 13.5A peak (so in theory you are in limits).
The voltage of 310V you are seeing is the panels open circuit voltage (39.43V) which is what happens when the inverter powers off the string (it goes open circuit)
Whilst their maximum current is just below the inverters maximum limit, the problem occurs because the panels are rated at 430W at 25C with 1000M3 of solar irradiance - they actually reduce in power as the temperature increases, but equally they are slightly more powerful as the temperature falls and so on a summers day they won't get much past their maximum power, but on a cold day at this time of year their power is just a little bit too high.
What that means is that panels produce more than the 13.5A limit the inverter has, and so the inverter will raise an alarm and shut the string down, as soon as the inverter works out that the power has fallen below it's maximum limit it will turn the string back on again, which is what you are seeing.
Whilst it sounds the same as clipping, it is a different thing - with clipping your panels are generating more power than the inverter is allowed to output (as you have an H1 5.0, your max power is 5 kW) so if you exceed 5kW the inverter will reduce the power point so that it maintains it's maximum power. What you are seeing is it exceed the maximum string current which results in an alarm and it turning off the string temporarily until it can safely turn it back on.
Ironically had the lower powered panels been installed you probably wouldn't have seen this problem.
So a couple of things to run through -
- It's not dangerous, the inverter is protecting itself from the over power limit and it will recover as soon as the power drops again.
- I would normally say speak to your installer about this to re-configure your strings, but as they are both maxed out there are no simple options, ideally the smaller panels would have been the better solution.
- But if it doesn't happen very often, and recovers quickly you should find that the problem reduces as the weather warms up and it likely won't happen at all in summer - in winter it won't happen either, it is just the 'goldilocks' point you are in at the moment with brand new panels, high solar elevation, strong sun but cold air temp and panels - so only likely to occur in April or October.
- As your panels age their power will (slowly) reduce, they will also get debris and dust on them, all of which will gradually reduce the maximum power they can ever achieve.
I would definitely mention it to your installer, they need to know and there maybe something they can do to limit it - but for the reasons I mentioned i'm hoping that the problem will remove itself naturally over time.