"PV Shading" in direct sun

[david94133]

I've noticed that my Classic 150 often goes into "PV Shading", and the wattage changes from ~900 to ~200 for a while, when there is no shading at all. It is a crystal clear day at 5000' elevation and no shading is occurring.

I don't monitor the classic all the time, so I'm not sure how often it is happening, but I've seen it about 4 times over the last few days.

Is this normal, a bug, a problem I need to fix ... ?

Thanks for any help you can provide.

-- David

[dapdan]

David,

you are not alone. I first noticed this issue about eight months ago and recent another member has brought it up. Check out these post and see if there is any similarity to what you are experiencing. It is some kind of bug with the controller IMHO.

http://midnitesolar.com/smf_forum/index.php?topic=594.0

http://midnitesolar.com/smf_forum/index.php?topic=364.0



Cheers...
Damani

[boB]

David, what is your battery voltage ??   Is it 12V ??

boB

[david94133]

The battery voltage is 12v. The solar is 96v.

Thanks for the help!

[epsgunner]

I'm interested in buying the Classic 150 (or Classic 150 Lite) shortly..

I plan on running a 12v bank and 12v (18v nominal) panels in series of 2's for 36VMP going in * 3 in parallel.. total of 6 panels..

My panels will have no shading unless a cloud passes (no trees) but this issue makes me nervouse..

Did anyone figure a resolution on this issue??

[Halfcrazy]

This has shown up on a couple occasions. These are very select and far between. But that said boB the lead Engineer has found the culprit and will be fixing it up in the code for the next release that should be happening soon.

Ryan

[boB]

Yes, and this Behavior does appear to happen more with 12V batteries for some reason.

You could change temporarily to another tracking mode like maybe Legacy until it is
fixed if it is happening too often.

boB

[epsgunner]

I read another post on here that said something about 'Dynamic' mode.. is that the same thing or something else..

[boB]

I read another post on here that said something about 'Dynamic' mode.. is that the same thing or something else..

Yes, Dynamic mode is one of the modes and should also work. 

boB

[dapdan]

Eps,

I am the first user of the classic that picked up this issue late last year. I don't think this is an issue that should make you or anyone nervous about purchasing the classic. The classic remains to be the best controller for your money today and the roll out of the lite makes it more so. Even though my controller operation in fast tracking mode was not ideal it works perfectly in Dynamic mode with no issues to date. I am right now planning the purchase of about 3 of the lites. If only my usual vendor has them to sell I would buy them right away.

Cheers...
Damani