question

fenix avatar image
fenix asked

Mppt 100-50 does not start

Hello

I notice that in morning the MPPT 100/50 does not produce watts

I see voltage going up but not wattage

If I close the breaker my breaker of the charger and solar then the controller start

Any help would be appreciated

MPPT Controllers
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

2 Answers
JohnC avatar image
JohnC answered ·

Hi Fenix. Not entirely clear on what you're doing there with your breakers, and you don't state your V's. First place to look..

..The mppt won't fire up until it sees >5V difference between the panel Voc and Vbat. In production that Voc changes to Vmp, and that can be a big step down in poor morning light, even as much as halving the Voc. Then the difference becomes only 1V for it to keep working. But if it can't maintain that it will falter and drop out.

How frequently it retries I can't say, but it won't be doing it instantly, and may wait at least a few minutes before reattempting. Victron mppt's seem to retrack Vmp every 10 min, so that's a possible guess. And your 'rebooting' with the breakers may just be prompting a fresh retry.

This will be very difficult to follow in real-time due to the speed it will happen, and even VRM graphs may miss these 'failed attempts'.

I hope this makes sense. Tell us your panel/batt V's when this is happening, and maybe we can do better if you think it's something else.



6 comments
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

adev avatar image adev commented ·

I thought after a cycle starts, the voltage difference required for continuation goes to 2v (not 1v)?

0 Likes 0 ·
fenix avatar image fenix commented ·

Hello

is this useful?

i have re-set the breaker at 8:59:40... then the solar start pushing Amp


0 Likes 0 ·
1571154616955.png (65.4 KiB)
JohnC avatar image JohnC ♦ fenix commented ·

Yeh, it's all clues, so is the info in your profile.

But ~20W from 450W of panel isn't much, even in poor weather. Doesn't show what happens later, but with those '12V' panels it should track the mpp down at least below 18V.

If it doesn't, maybe a fault (heaven forbid) or it's being limited by your other kit. Does your 'Mppt State' show 'Bulk' or 'External Control' (or ESS)?

Forgive me some general observations. It's not nice to have pbs at such a low V. And if you can, string your panels to a higher V for best results.

And a question for my benefit - how do you get < 1 min time periods on VRM??

0 Likes 0 ·
fenix avatar image fenix JohnC ♦ commented ·

JohnC

for the VRM.. I set the VRM to have one second.... in the graph I did a Zoom

A

0 Likes 0 ·
fenix avatar image fenix JohnC ♦ commented ·

JohnC

the solar panel are on my roof of the camper, there is a lot of shade created by the accessories, they are flat on the roof. I wish I could make them inclinable but did want to drill holes on the roof. my ideal was to have as many solar panel to catch what the sun could give me .

I connect them in parallel because of that.


Tks again for your help

here is snap shoot of the last 30 days


0 Likes 0 ·
Tim from Eat Sleep Van avatar image
Tim from Eat Sleep Van answered ·

I too am having this problem.

It happens occasionally, and I can't figure out a reason. Just now for example, I'm in full sun, after turning the breaker off/on again my 3x300W panels in series are outputting 400W @ 97V. Looking at the charts it did start earlier, then stopped for some reason until I intervened. Here's my VRM account: https://vrm.victronenergy.com/installation/16649/advanced


2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.