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Overvoltage on Victron MPPTs?

DVD

New member and getting older
Joined
Jul 24, 2023
Messages
217
Location
California
I’m looking at series combining 2 residential panels to a Victron 100/50 SmartSolar charge controller. Under STC the Voc of each panel is 49 volts. Or 98 volts if series connected. At low ambient temperatures this will increase and exceed the 100/50 input specs.
Has anyone actually seen (experienced first hand) what, if any, harm happens if Voc is say 10-15% above the rated specification.
I’ve seen that Victron products will throw an error on out of spec conditions, but I’ve not seen any catastrophic damage if the error conditions are not too severe.
Experiences?
 
No. I've never seen it because I'm not an idiot anymore. I put 3S 45Voc panel on a 150V controller and caught it before the cold temps pushed Voc over 150V. Upgraded to a 250/100.

MPPT Voc limits are NEVER EXCEED. This is not just a Victron thing. This is an every MPPT on the planet thing.

No. At low ambient temps, it will not over-volt the controller. It will over volt the controller at 20°C using NEC tables. I consider 20°C a very comfortable temperature. I'm often enjoying it in short sleeves and shorts.

Absolutely, positively don't do it. If it survives, the unit will log any over-voltage, and your 5 year warranty is void.

This evasive douche managed to cook multiple Victron MPPT controllers. Note how is video is gone, and he refused to post specifics about his 3S panels:

 
No. I've never seen it because I'm not an idiot anymore. I put 3S 45Voc panel on a 150V controller and caught it before the cold temps pushed Voc over 150V. Upgraded to a 250/100.

MPPT Voc limits are NEVER EXCEED. This is not just a Victron thing. This is an every MPPT on the planet thing.

No. At low ambient temps, it will not over-volt the controller. It will over volt the controller at 20°C using NEC tables. I consider 20°C a very comfortable temperature. I'm often enjoying it in short sleeves and shorts.

Absolutely, positively don't do it. If it survives, the unit will log any over-voltage, and your 5 year warranty is void.

This evasive douche managed to cook multiple Victron MPPT controllers. Note how is video is gone, and he refused to post specifics about his 3S panels:

You’re a good member and I appreciate the candor, but I’m still unconvinced, given Victrons normally excellent engineering (Orion notwithstanding). Maybe I’ll try with a spare 100/20 if I don’t hear back from others
 
Please do, rig a camera with audio aimed at the capacitors inside your MPPT, and post it here:


"New member and getting older" - but not wiser?

If you really want to do this, just buy a Midnight Classic.
(Sunshine's "This is an every MPPT on the planet thing." was just slightly exaggerated.)

Good engineering is telling customers how to stay safe.
Good engineering is incorporating "black box" functionality for when customers push things.
 
Please do, rig a camera with audio aimed at the capacitors inside your MPPT, and post it here:


"New member and getting older" - but not wiser?

If you really want to do this, just buy a Midnight Classic.
(Sunshine's "This is an every MPPT on the planet thing." was just slightly exaggerated.)

Good engineering is telling customers how to stay safe.
Good engineering is incorporating "black box" functionality for when customers push things.
I’m inclined to see and post what happens… it’ll be the spare 100/20 I have. I’ll probably take one of my 48 volt racks offline and add a couple 30 volt lab supplies to run the input voltage. That way I can limit the current in case there’s an OOPSY.
More to come, but tomorrow relatives are visiting for who knows how long.
My other forum tag line is “Learn by doing, learn more by making mistakes” 😉😉
 
I’m inclined to see and post what happens… it’ll be the spare 100/20 I have. I’ll probably take one of my 48 volt racks offline and add a couple 30 volt lab supplies to run the input voltage. That way I can limit the current in case there’s an OOPSY.
More to come, but tomorrow relatives are visiting for who knows how long.
My other forum tag line is “Learn by doing, learn more by making mistakes” 😉😉
Well there is "learn more by making mistakes" which can be kind of wise. Space-x does it all the time :)

But there is also "Read the freaking manual" and "I told you so".

When the manufacturer tells you not to exceed the limit and there are examples on hand over and over then that isn't learning.

That's a "here's your sign" situation :)


If you want to "test" it with no cost involved and or killing equipment for no real reason then try this :

On a cold day (the coldest your going to experience at your location) take a volt meter and hook to the wires that you would of attached to the pv input on the controller but don't connect them to the controller.

See if it exceeds the pv voltage limit of the controller. That is the only way your going to know for sure if its safe.

I just use a simple math formula to play it safe with my stuff. pv max volts (voc) of the panels times the amount of panels I have times 1.2

If that is less than max pv input voltage limit of the controller I know it will keep the magic smoke INSIDE the controller.
 
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I’ll post when I finish. So far no one that has actual experience has replied. Maybe I’ll have to answer my own question.
And YES by the way as an SEL pilot I observed the “never exceed” airspeed specified on the Cessna 170 I regularly flew, but always wondered what would happen if I went over by a bit 🌞🌞🤣🤣 I can be a little more bold with a $50 MPPT than with my life.
 
I’ll post when I finish. So far no one that has actual experience has replied. Maybe I’ll have to answer my own question.
And YES by the way as an SEL pilot I observed the “never exceed” airspeed specified on the Cessna 170 I regularly flew, but always wondered what would happen if I went over by a bit 🌞🌞🤣🤣 I can be a little more bold with a $50 MPPT than with my life.
Flutter would of been your main concern going over the speed limit. A bit over isn't going to do much. Enough over your going to loose control or even the control surfaces then the wing pitches up and folds :)

Of course on that plane your going to need to put it in a dive to get up enough speed probably. Bad part about flutter if you go into it fast enough you don't get the warning feedback to let you know somethings wrong before you in so far its game over.
 
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Waiting for your video with confimred over voltage, which will confirm that the controller was coerced into letting out the magic smoke!

As someone who has replaced new charge controllers and not gotten the benefit of the warranty for clients because they failed to read the manual and comprehend the "do not exceed the VOC of the controller" warning.

I'm willing to relearn not to do this on your dime!:coffee:🍿
 
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You’re a good member and I appreciate the candor, but I’m still unconvinced, given Victrons normally excellent engineering (Orion notwithstanding). Maybe I’ll try with a spare 100/20 if I don’t hear back from others
Careful you blow the hell out of it,which might be ok in colder times/months,but now?:ROFLMAO:
 
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