noelex
Well-Known Member
Ignore the load output feature and terminals.
Make sure you have a fuse between the controller and the batteries.
Make sure you have a fuse between the controller and the batteries.
Solar MPPT Question
- Thread starter Major_Clanger
- Start date
Major_Clanger
Well-Known Member
That's great, thanks for the clarification.
thinwater
Well-Known Member
As for partial charging, they are talking about cruisers that cycle the battery well below full charge. That's not good for lead batteries, but a few cycles is not harmful (do try hard to stay about 45%--very low charge is harmful). However, it sounds like you will be using it as a battery maintainer most of the time, and the battery will be fully charged most of the time. No worries.
NBs
Well-Known Member
You're probably right—on a sunny day, the V values are often around 17–20, and the signal-to-noise ratio isn't as good as it was when the screenshot was taken. Today it's cloudy and raining lightly—here's a new screenshotThat is a very nice display, but why is solar panel voltage so low? Even on a cloudy morning the Vmp should be 17V+ for a typical "12V panel" unless it is very hot.
The other interesting point is the display suggests the MPPT controller performing the voltage conversion so efficiently that even after also allowing for its self consumption the loss between input and output is less than 1W.
The reality is MPPT controllers, while efficient, have more significant losses than the display is indicating.
Many manufacturers calibrate their controllers in this way to exaggerate the efficiency. On occasions, some will even indicate a higher wattage output than the input. A perpetual energy machine
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noelex
Well-Known Member
That looks much better.
Major_Clanger
Well-Known Member
noelex
Well-Known Member
It looks like you have purchased the non-Bluetooth version of the controller. This may have been deliberate. The Bluetooth version is slightly dearer and not everyone feels the difference is worthwhile.
However, the Bluetooth function is very useful, especially with its ability to easily alter the charging settings and to troubleshoot. I would normally recommend this option.
Before it is installed, may be the last chance to organise an exchange if this was an accident. The two versions look almost identical, so it is easy to purchase the wrong model without realising the difference.
As a final option Victron makes a plug in accessory that adds the Bluetooth connectivity. I believe it is more expensive than the price difference between the two models but it may be a solution if you wanted the Bluetooth functionality but cannot exchange the controller.
However, the Bluetooth function is very useful, especially with its ability to easily alter the charging settings and to troubleshoot. I would normally recommend this option.
Before it is installed, may be the last chance to organise an exchange if this was an accident. The two versions look almost identical, so it is easy to purchase the wrong model without realising the difference.
As a final option Victron makes a plug in accessory that adds the Bluetooth connectivity. I believe it is more expensive than the price difference between the two models but it may be a solution if you wanted the Bluetooth functionality but cannot exchange the controller.
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Major_Clanger
Well-Known Member
Thanks but the purchase was deliberate. I'll probably only deploy the panel when I'm on board so Bluetooth would be of little use.
PaulRainbow
Well-Known Member
But you would equally only use the Bluetooth functions when you are onboard. Without Bluetooth how will you set the charging parameters ?Thanks but the purchase was deliberate. I'll probably only deploy the panel when I'm on board so Bluetooth would be of little use.
Major_Clanger
Well-Known Member
Ha-ha, yes that's very true. I don't want to over-complicate things for myself - all I want it to do is charge the batteries and stop when they're full. If what I've bought will do that then I'm happy.
PaulRainbow
Well-Known Member
Non Bluetooth controllers are really designed to be part of networked installations where they can be configured and monitored by something such as a Cerbo GX. You have no way of changing the settings or monitoring what it's doing to your batteries.
Major_Clanger
Well-Known Member
So does that mean the MPPT will allow the panel to keep charging the batteries even once they're full?
PaulRainbow
Well-Known Member
How big is the panel and what batteries do you have ?
Major_Clanger
Well-Known Member
Panel is 100w and there are two leisure batteries, 100ah & 80ah, wired in parallel.
PaulRainbow
Well-Known Member
The default setting for the controller is 14.4V Absorption and 13.8V float. 13.8V is a little on the high side, but if you're not leaving the panel charging for an extended time while you're away from the boat you'll probably be OK. I would still swap it for the Bluetooth one.
RupertW
Well-Known Member
I guess that’s the difference- we leave the boat charging for many months unattended (probably 11 months alas this year) and I’d hate to have float above 13.3V for our FLA bank.
GunfleetSand
Well-Known Member
Where from?
Major_Clanger
Well-Known Member
One final question if I may..... Can I wire the panel to the main pos and neg busbars, or does it have to go straight to the batteries after the MPPT?
PaulRainbow
Well-Known Member
Normal practice is to connect before, or at, the isolator switch, so it can charge the batteries if the main isolator is off. This is also true with mains chargers.
PaulRainbow
Well-Known Member
I see you also asked this on the Victron forum.
Nothing wrong with doing so, of course. Many of the answers on there are completely nonsense.
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