How much power are you solar panels generating?

[Tony Brooks]

25 minutes ago, Rob-M said:

My understanding, and how I use the Victron solar app, is that the min voltage is the lowest reading of the batteries in the last 24hrs.  Ours usually shows 12.5v on the min when I get up in the morning.

 

In that case, it is about as much use for battery monitoring as a chocolate fireguard. If Heather has the funds then I would suggest that she gets a proper battery monitor and learn how to set it up, how to use it, and which readings are likely to be lies.

[DShK]

10 minutes ago, Tony Brooks said:

 

In that case, it is about as much use for battery monitoring as a chocolate fireguard. If Heather has the funds then I would suggest that she gets a proper battery monitor and learn how to set it up, how to use it, and which readings are likely to be lies.

That's just for that summary view. You can view the current and entire battery voltage history in a graph form too. Whether it is an ideal battery monitor given it could have considerable cable length between it and the batteries is another question...

 

Edit: they have a smart battery sense so volt drop should not be an issue, as it feeds the solar controller the voltage read close to the battery.

Edited August 10, 2023 by DShK

[Tony Brooks]

27 minutes ago, DShK said:

That's just for that summary view. You can view the current and entire battery voltage history in a graph form too. Whether it is an ideal battery monitor given it could have considerable cable length between it and the batteries is another question...

 

Edit: they have a smart battery sense so volt drop should not be an issue, as it feeds the solar controller the voltage read close to the battery.

 

In that case, then the OP would be better advised to use the last point on the graphs or the instantaneous readings to see what is going on.

Edited August 10, 2023 by Tony Brooks

[Hevs]

1 hour ago, Tony Brooks said:

 

I agree, and I am not biased ----------- apart from against those who do not conduct themselves like Heather.

You guys 😊.

 

Honestly just desperate for answers so it's not without a catch 😁

[Hevs]

1 hour ago, Tony Brooks said:

 

I think that depends upon when the reading was taken. 13.2 charging voltage suggests to me that they are still drawing charge, but unless we know the potential solar output we don't know if it is 13.2 volts because it is still drawing lots of current or 13.2 because the panels can only produce that voltage (shade, low sun angle, etc.)

I was charging my laptop at the time and plugging in to the shoreline.

[Hevs]

1 hour ago, DShK said:

Odd question but are you plugged into a shoreline? You said you were previously. The low output and consistent output from the panels looks like my output when I was using lead batteries and plugged into a shoreline. The fact that your minimum voltage is 13V leads me to believe you're plugged in, as this would drop lower over night.

 

If this is the case, the charger and solar are competing to top your batteries up. There isn't an easy solution to give your solar panels priority, other than manually plugging in when the solar output isn't keeping up with your needs.

Yes I am.

[Hevs]

59 minutes ago, DShK said:

I'm lazy so I've programmed my system so that the shoreline will be used automatically if the battery SoC drops to a certain point. But this isn't a particularly easy solution for a noobie just getting to grips with things. Perfectly doable though, especially as they have victron equipment.

This is really interesting! Perhaps something for me to look in to with my techy brother in law. 😊

[rusty69]

58 minutes ago, DShK said:

I'm lazy so I've programmed my system so that the shoreline will be used automatically if the battery SoC drops to a certain point. But this isn't a particularly easy solution for a noobie just getting to grips with things. Perfectly doable though, especially as they have victron equipment.

I bought my first Victron bit of kit a few weeks ago (MPPT and battery sense), I am very happy with it. It is so configurable, and easy to view via bluetooth (and Venus OS). I am going to buy a smart shunt, and forget about the old style shunt/meter based system that I can't see, A. because it is 30 ft away and B. Becasue its too damn small to see.

 

Well done Victron.

[Tony Brooks]

8 minutes ago, Hevs said:

I was charging my laptop at the time and plugging in to the shoreline.

 

As we have since had explained, the voltage reading you showed occurred some time in the last 24 hours, probably in the middle of the night. It seems that you can find the instant voltage and current readings such as you would get on a meter on your display, and those will be far more useful. I suspect when you have the charger and laptop running, the voltage would have been above 14.4 volts.

[MrBean]

The data you have provided from the battery monitor shows that on the day where you generated the most power the minimum voltage of the battery was much lower than the other days. Therefore, the battery had the capacity to absorb much more power. See the value underlined red below. When you look at the minimum voltage over the last few days, in you other screenshot, the minimum voltage is barely below 13V, hence the batterys were unable to absorb a lot of power.

 

 

 

Before I get told off, the voltages provide an indication of what amount of power the batteries were able to absorb. The low voltage could have been an instantanous dip when you turned on a heavy load, but if not on for a long time then the battery may not have discharged much of course!

Edited August 10, 2023 by MrBean
For clarity, spelling

[DShK]

32 minutes ago, Hevs said:

Yes I am.

There's your answer then. Unplug from the shoreline and you'll see the output go up. I would get to proper grips with understanding proper battery charging before you do though otherwise you'll nuke your batteries and need to replace them. See the thread I linked before.

 

29 minutes ago, Hevs said:

This is really interesting! Perhaps something for me to look in to with my techy brother in law. 😊

There's a few ways you can do it.

 

The way I'm doing it - (more complex, costly - but more configurable, important for my particular setup)

You'll need something to allow everything to communicate - either a cerbo GX or a raspberry pi (plus some special cables) loaded with Venus OS (Large firmware). You'll then need install NodeRed and use this to program the system to turn on the charger when voltage dips below a certain threshold. For better results, install a victron battery shunt and monitor the state of charge. You can turn the charger off again when the batteries are fully charged this way too.

 

I believe you can also use something called an "Assistant" which is some logic you can load into the firmware of your Inverter/Charger (assuming you have a multiplus or similar). I believe you can program this kind of logic in. You'll need one of these cables and a laptop https://www.12voltplanet.co.uk/victron-energy-vedirect-to-usb-interface.html

 

https://www.victronenergy.com/live/assistants:start

 

And now that I think about it, if you use that cable, and the victron connect app. I think if you go into the inverter/charger settings (password is zzz) I think you can plug in "conditional charging" or something. I think that will only turn on charging when a voltage threshold is met.

 

 

Edited August 10, 2023 by DShK

[rusty69]

6 minutes ago, DShK said:

There's your answer then. Unplug from the shoreline and you'll see the output go up. I would get to proper grips with understanding proper battery charging before you do though otherwise you'll nuke your batteries and need to replace them. See the thread I linked before.

 

There's a few ways you can do it.

 

The way I'm doing it - (more complex, costly - but more configurable, important for my particular setup)

You'll need something to allow everything to communicate - either a cerbo GX or a raspberry pi (plus some special cables) loaded with Venus OS (Large firmware). You'll then need install NodeRed and use this to program the system to turn on the charger when voltage dips below a certain threshold. For better results, install a victron battery shunt and monitor the state of charge. You can turn the charger off again when the batteries are fully charged this way too.

 

I believe you can also use something called an "Assistant" which is some logic you can load into the firmware of your Inverter/Charger (assuming you have a multiplus or similar). I believe you can program this kind of logic in. You'll need one of these cables and a laptop https://www.12voltplanet.co.uk/victron-energy-vedirect-to-usb-interface.html

 

And now that I think about it, if you use that cable, and the victron connect app. I think if you go into the inverter/charger settings (password is zzz) I think you can plug in "conditional charging" or something. I think that will only turn on charging when a voltage threshold is met.

I reckon you should do a "victron primer" so us idiots can follow the raspberry pi/cerbo thing,node red and hardware integration. 

 

I'm getting there slowly, but by brain hurts. 

[Rob-M]

1 hour ago, Tony Brooks said:

 

In that case, it is about as much use for battery monitoring as a chocolate fireguard. If Heather has the funds then I would suggest that she gets a proper battery monitor and learn how to set it up, how to use it, and which readings are likely to be lies.

I like to know the lowest voltage our batteries have gone down to over a daily period so I like that feature.  I do have a NASA BM-2 monitor as well.  As our cheap, sealed LA batteries are 10 years old it seems to work alright for us.

[Tony Brooks]

5 minutes ago, Rob-M said:

I like to know the lowest voltage our batteries have gone down to over a daily period so I like that feature.  I do have a NASA BM-2 monitor as well.  As our cheap, sealed LA batteries are 10 years old it seems to work alright for us.

 

That is fair enough, but it does not show the state of charge unless you know exactly what was going on at the time it was taken. While you were learning how to monitor and look after batteries, I bet the readings on the BM-2 for volts and amps were more useful than the Victron app.

[Rob-M]

2 minutes ago, Tony Brooks said:

 

That is fair enough, but it does not show the state of charge unless you know exactly what was going on at the time it was taken. While you were learning how to monitor and look after batteries, I bet the readings on the BM-2 for volts and amps were more useful than the Victron app.

Yes, I only use the min value on the Victron app to see how low the voltage went which is usually the from the fridge overnight.  During the day when solar is charging I compare the app readings for instantaneous volts and amps with the BM-2.

[Karen Lea Rainey]

If you've got 2 x 400 w panels, then you wont need shoreline in the summer, you can unplug it and let you're solar panels do the maintaining of the batteries.

I have the same system and if I'm not on the boat with the fridge running, TV on, lights on etc then I get about 30 w produced maximum over the day, the batteries remain fully charged and throughout the day stay around 13.8v (5 batteries in total)

4L +1S.

Go onto "trends" on your victron and you will hopefully see that when you are using serious power like the fridge, then the solar graph spikes upwards to compensate for a voltage drop. Then when the fridge compressor rests the solar wattage drops off very quickly.

Basically 'if you ain't using any electricity, your solar doesnt need to generate anything.

Sounds like your solar is working correctly to my eyes.

[Tony Brooks]

8 minutes ago, Karen Lea Rainey said:

I get about 30 w produced maximum over the day,

 

Sorry, but your units are wrong. If you are measuring over a day, then you need time in the units, so watt-hours. 30 watt-hours is about 2.5 amp hours. That is hardly credible unless you only have a small panel.

[PeterF]

1 hour ago, MrBean said:

The data you have provided from the battery monitor shows that on the day where you generated the most power the minimum voltage of the battery was much lower than the other days. Therefore, the battery had the capacity to absorb much more power. See the value underlined red below. When you look at the minimum voltage over the last few days, in you other screenshot, the minimum voltage is barely below 13V, hence the batterys were unable to absorb a lot of power.

 

 

 

Before I get told off, the voltages provide an indication of what amount of power the batteries were able to absorb. The low voltage could have been an instantanous dip when you turned on a heavy load, but if not on for a long time then the battery may not have discharged much of course!

I will add more important information to the note above on voltage. If you look on every day the voltage is reaching around 14.4V so maximum charge voltage.

Secondly, the bar chart for each day is showing a lower section in white for bulk charging where the battery is accepting lots of charge, a light blue bar which is narrow which is absorption which is the final charge at 14.4V that tops the last 10% or so of charge. Then there is a larger upper mid blue section which is float, which occurs when the batteries are full. Therefore, I agree with other peoples view, your batteries are limiting the energy received by solar as they are nearly full due to lower loads or charging from shore.

Edited August 10, 2023 by PeterF

[DShK]

1 hour ago, rusty69 said:

I reckon you should do a "victron primer" so us idiots can follow the raspberry pi/cerbo thing,node red and hardware integration. 

 

I'm getting there slowly, but by brain hurts. 

 

I'd love to contribute back to the community like that, given the amount of help I've received on here (definitely from yourself!). I'll have a think about the best way to present the info, and get it typed up when I have some free time. I might dual purpose it as a brief on how to mid-budget a lithium setup too.

[rusty69]

3 minutes ago, DShK said:

 

I'd love to contribute back to the community like that, given the amount of help I've received on here (definitely from yourself!). I'll have a think about the best way to present the info, and get it typed up when I have some free time. I might dual purpose it as a brief on how to mid-budget a lithium setup too.

Hey, I was only joking. Though it would be a fantastic resource. No pressure 😂

[DShK]

6 minutes ago, rusty69 said:

Hey, I was only joking. Though it would be a fantastic resource. No pressure 😂

My old marina tried to sell me on a "black box" for solar charging the way OP wants. Said it was underdevelopment. I wonder if it was just going to be an overpriced rapsberrypi?

 

I think the victron units are probably under utilised, so more more (pun not intended) to the boaters the better. I had a mastervolt system on my boat when I bought it. I can't believe how much better the victron units are, for half the price...

[rusty69]

3 minutes ago, DShK said:

My old marina tried to sell me on a "black box" for solar charging the way OP wants. Said it was underdevelopment. I wonder if it was just going to be an overpriced rapsberrypi?

 

I think the victron units are probably under utilised, so more more (pun not intended) to the boaters the better. I had a mastervolt system on my boat when I bought it. I can't believe how much better the victron units are, for half the price...

It's like a lot of things in life, there are often cheaper methods of doing things than the commercial stuff, but it is rarely straight forward, and often frustrating when the install doesn't follow the script. The information is liable to change when file locations etc are moved, and DIY data cables need making up. 

 

Chuck in some command line and some node red and you can see why people pay for an all singing and dancing professional install. 

 

Victron do seem to be ahead of the game in terms of networking and ease of use though. 

[DShK]

7 minutes ago, rusty69 said:

It's like a lot of things in life, there are often cheaper methods of doing things than the commercial stuff, but it is rarely straight forward, and often frustrating when the install doesn't follow the script. The information is liable to change when file locations etc are moved, and DIY data cables need making up. 

 

Chuck in some command line and some node red and you can see why people pay for an all singing and dancing professional install. 

 

Victron do seem to be ahead of the game in terms of networking and ease of use though. 

 

Depends on how much you enjoy doing these things I guess! Half the attraction of moving onto a boat for me was fudging and fettling.

 

I imagine a "professional" would charge a lot of money for this stuff too. After you've waited months for them to be available. And then when they've cocked something up, you don't know how to deal with it.

 

I don't think once you've got all the right info the victron stuff is too bad. You don't need to make custom cables (in fact is is very much advised not to). And it's not like you've got to compile Venus OS from source code modifying it to target the pi. Obviously we all have different strengths but I think if I amalgamated all the info in one place clearly, it should be accessible to most (with reasonable understanding of boat 'leccy)

[rusty69]

7 minutes ago, DShK said:

 

Depends on how much you enjoy doing these things I guess! Half the attraction of moving onto a boat for me was fudging and fettling.

 

I imagine a "professional" would charge a lot of money for this stuff too. After you've waited months for them to be available. And then when they've cocked something up, you don't know how to deal with it.

 

I don't think once you've got all the right info the victron stuff is too bad. You don't need to make custom cables (in fact is is very much advised not to). And it's not like you've got to compile Venus OS from source code modifying it to target the pi. Obviously we all have different strengths but I think if I amalgamated all the info in one place clearly, it should be accessible to most (with reasonable understanding of boat 'leccy)

Well, you have my vote. 

 

All we need is a second 😂

 

Or better still, a poll. You can't beat a good poll. 

[Rob-M]

Just now, rusty69 said:

Well, you have my vote. 

 

All we need is a second 😂

 

Or better still, a poll. You can't beat a good poll. 

I'll second it.  Still trying to decide whether to switch to lithium's and replace my separate inverter and charger with a combined Victron unit.  Quite fancy having a cerbo GX with display panel.