Morning all,

Please advise, I have a Luxpower 12K, with 5 CFE 5100 batteries.

It constantly complains about VBus over range,

 

I have 2 Solar strings, one with 11 panels on MPPT1 and one with 7 panels on MPPT2

 

Now, the errors, is it because of high voltage from string 1 or a battery issue? From what I could see the voltage range is up to 600v?

 

Screen prints attached,

 

Thanks!

Dion

 

 

 

 

13 minutes ago, dionvdberg said:

I have 2 Solar strings, one with 11 panels on MPPT1 and one with 7 panels on MPPT2

I don't know your inverter so I'm just speculating here, I'd say you are sailing rather close to the wind on the 11 panel end, if I were you, I'd shorten the 11 panel string to 9 and give it a day or two and see if the errors still occur.

Ideally if someone comes up with any sort of problem like this, it would be cool if you could specify what the inverter's MPPT's are specced at, Tension and Current wise and also specify what you solar panels are specced at, you didn't even mention what model/make they are, so there is no way for anyone to really comment with 100% accuracy on you problem.

Vbus, I'd think refers to the high voltage DC side, the solar end, but I could be wrong.

Again, I suggest shortending the 11S string to 9S and seeing what happens, Voltage on the MPPT side is not under the inverters control, only current allowed to flow, this directly impacts the Voltage, but not to the degree that the MPPT has control over the Voltage on the input end.

Edited November 11, 20223 yr by Kalahari Meerkat
speeling and grammatika

Thanks,

The panels are 465W Bifacial panels,

** Just read the specs now, seems like MPPT range is 120-500v, so probably the issue?

DC Voltage range is 100-600v

 

Dion

 

Edited November 11, 20223 yr by dionvdberg

43 minutes ago, dionvdberg said:

** Just read the specs now, seems like MPPT range is 120-500v, so probably the issue?

Personally I'd try to remain slightly below the 500V side of the MPPT, that would give one a little bit of leeway when clouds disappear and the panels go into overdrive mode for a little while... so aiming for 450V is probably a good number in your case, heck , if you end up with 460V or 470V, that's also fine...

These Akcome 465W BiFacial seems to be Voc = 53.65V and Vmp = 45.5V if these were yours then they'd be sitting at just shy of 600V with no load and at app. 500V with load, too much, I'd say, you'd want to be < 500V at no load/Voc ideally. So 9 of these would be 53.65 * 9 = 482.85 without load and I'd call this safe and 45.5 * 9 = 409.5V at maximum power production, this I'd call perfectly safe to be well withing the specified parameters of your inverter.

There are, I am sure, other bifacial ones and the ones I chose are probably not yours, but as an example, it should give you an idea on how to calculate things out...

You are 100% correct, they are Akcome panels,

Ok, thanks alot for the advice, time to get in/on the roof again... 🙈

 

Cheers

Dion

13 minutes ago, dionvdberg said:

Ok, thanks alot for the advice, time to get in/on the roof again... 🙈

careful doing this in daylight... a couple of hundred Volt at up to nearly 11A can be lethal... maybe throw some blankets or something to totally shade the panel string you'd be working on, if you will be doing this during daylight hours...