'Plug and play' solar panels.

[James1000]

So got the van back from the garage and decided to test the new SARONIC 150w. I also connected the BT battery monitor before I started. I can’t quite work out what is going on. The key reason for the solar is to maintain the fridge so that is my test!

62% Battery at start
100% Battery within two hours
At the same time the fridge was running and it was all working really well.
Now the solar is disconnected I am literally sat here watching the battery % tumble

My Dometic CRX65 always runs and cuts out but never cuts out for long and fires up again I am not sure if this is normal I am guessing so for a compressor

Should a battery charge that quickly ?

I would expect a fridge to last two days but at this rate it will be a matter of hours so is this an isssue with a two year old battery

Answers on a post card please ?

 

[Dellmassive]

Looking good...

But you need to let the battery monitor run for a couple of days... to get a baseline for your system...

Then see what effect adding the solar gives.

And what effect running the fridge has.

Hopefully the net effect will be fridge running all weekend.

Don't pay too much attention to the % the BM2 gives.... its the general trend over 24hrs that is more relevant.

Post a 24hr shot tomorrow.

 

[AussieMick]

May help to charge battery fully on a 240v charger then set your monitor to 100% when you are drawing no power.
This will give a more accurate state of charge, soc, reading.
This is what I have to do on my monitor initially so maybe required on yours.

 

[Dellmassive]

May help to charge battery fully on a 240v charger then set your monitor to 100% when you are drawing no power.
This will give a more accurate state of charge, soc, reading.
This is what I have to do on my monitor initially so maybe required on yours.

Yes agreed . . . but the BM2 monitor is just a voltage logger that assumes the SOC from the voltage using an algorithm. (ie you cant set it to 100%, it just displays what it likes)

The "charge and set to 100%" is the correct way for shunt style monitors like the Victron BMV712 etc and others..

 

[James1000]

Thanks - I agree and was just heading out to charge it over night - also get fridge up to temp and then disconnect in the morning or do I switch to solar ?
Found some white powder by battery so dubious!

 

[Dellmassive]

well we arnt in full summer yet . . . . so solar yield is not great.

...

id fully charge the battery for 24hrs with a smart charger.

then leave the van for a day and take a screen shot . . . . that will be your charged basline.

then add the solar for a day . . . then take another screen shot. (bassline + solar charge)

then switch on the fridge (with the solar) on the third day . . . (bassline + solar charge + fridge running)

post the screen shots so we can see how effective it all is.

also post a few pics of your leisure battery and DC-DC if you have one. . .

and your mains smart charger - the more pics the merrier.

 

[AussieMick]

Fair enough, I have a Victron bmv712 so that's all I know about , how does this one get the accurate soc .
I assume from initial settings like ah capacity of battery and things like that.
Is that how it calculates soc?

 

[James1000]

So it’s all fairly tight under the seat and all installed by the converter. I have never really had a need to look under there before so it’s new to me
And there haven’t been any issues, I’m concerned by the discharge on the right as for the other bits I’ve no idea. But that fridge used to run for 2-3 days - it was in last summers heat I and no EHU I noticed I wasn’t getting a long weekend hence the decision to go solar.

 

[Skyliner33]

well we arnt in full summer yet . . . . so solar yield is not great.

...

id fully charge the battery for 24hrs with a smart charger.

then leave the van for a day and take a screen shot . . . . that will be your charged basline.

then add the solar for a day . . . then take another screen shot. (bassline + solar charge)

then switch on the fridge (with the solar) on the third day . . . (bassline + solar charge + fridge running)

post the screen shots so we can see how effective it all is.

also post a few pics of your leisure battery and DC-DC if you have one. . .

and your mains smart charger - the more pics the merrier.

We are only 3 weeks away from the 'longest day'. :/

 

[James1000]

And on only had one day over 20degs!!

We are only 3 weeks away from the 'longest day'. :/

 

[Dellmassive]

yep . . . rubbish weather so far this year. . . . (with regards to solar)

lets hope it gets better in June.

 

[Dellmassive]

Fair enough, I have a Victron bmv712 so that's all I know about , how does this one get the accurate soc .
I assume from initial settings like ah capacity of battery and things like that.
Is that how it calculates soc?

here, have a look at the BM2.

a worthy addition to any 12v system . . .

it basically loggs the Voltage over time . . . mins,hours,days,weeks,months etc etc.

https://amzn.to/3oJ7rNf

.

• ✔Compatible with all 12-volt vehicle batteries;Voltage: 9-16V
• ✔Free app for both iOS & Android, IOS: IOS 7.1 and Later Available: Android 4.3 and Later
• ✔Easy to use:Connect with battery directly, no code,It provides a quick reading to determine if a vehicle battery needs a jump or replacing and also the alternator output status. Various Colored LEDs indicate the battery or the alternator status.
• ✔Check battery state on phone APP via Bluetooth 4.0 when device is installed
• ✔App Name: Battery Monitor BM2, please scan machine backup or user manual scan code to download software
• ✔WIDELY APPLICATION: Our auto battery monitor compatible with all 12-volt vehicle batteries;Voltage: 9-16V;the tester will scan the battery and get the results in seconds, including the State of Health, the State of Charge, the Internal Resistance and the Testing Conclusion (Poor, Good, Great). All types of 12V 100-2000CCA lead acid batteries can be tested, including Regular Flooded, AGM Flat Plate, AGM Spiral, GEL and EFB
• ✔WIDELY COMPATABILITY :The car battery tester offers free app for both iOS & Android, IOS: IOS 7.1 and Later Available: Android 4.3 and Later

• ✔BlUETOOTH CONNECT & SUPER EASY TO USE:The bluetooth battery load tester check battery state on phone APP via Bluetooth 4.0 when device is installed;connect this auto battery monitor with battery directly, no code,It provides a quick reading to determine if a vehicle battery needs a jump or replacing and also the alternator output status. Various Colored LEDs indicate the battery or the alternator status.
• ✔EASY DATA ACCESS:Compared with other normal digital battery tester device,our battery monitor supprot bluetooth,you could access your car bettery information directly with your phone,clear and easy access,other's are more trouble ,need to use traditional methods to connect to computer and then could download your car battery iformation.
• ✔100% MONEY BACK GUARANTEE & LIFETIME SERVICE:Our products are manufactured by experienced factory which specially produce car battery tester voltmeter,we standby our products.

.

++++


have a look here too:

Battery Monitoring -- How I Done It --

Battery Monitoring -- How I Done It -- Part #1 Battery monitoring is a very important part of your 12v system . . . . whether its just the vans starter battery or your leisure setup keeping an eye on the power in your battery bank will keep you from breaking down and make sure your weekends...

www.t6forum.com

++++

 

[Skyliner33]

yep . . . rubbish weather so far this year. . . . (with regards to solar)

lets hope it gets better in June.

View attachment 116756

Yep, and already in the part of the year where we never get true night time. Only twilight at night.

 

[James1000]

Just knew something wasn’t right so decided a new battery was needed, on removing the seat it became very obvious this was right!

Put new battery in and wow what a difference, I made sure it was charged and freezer up to temp, and have just left it on 12v.

12 hours later the battery is still on 95% . Ok so we are not suffering a heatwave to challenge the freezer but I got the solar to manage the off grid which it certainly will do but at this rate I won’t need it ha!!

Blue is the old battery red is the new!!

 

[Dellmassive]

That looks much better....

 

[James1000]

Just an update for interest only. With the new leisure battery charged - fridge up to temp and on freezer setting and with nothing else on I just left it all weekend. And so from Thursday pm to Monday am that fridge has run perfectly and without any issues and the battery has lasted easily.
The question is - why the hell did I buy 150w solar panel. Well I’m not sure the heat challenged the fridge and there was no other usage, phones, lights TV etc

So now I’m experimenting to see if the solar on 2/3 panels in the windscreen will give me anything.

This is the parked up scenarios

 

[Dellmassive]

Just an update for interest only. With the new leisure battery charged - fridge up to temp and on freezer setting and with nothing else on I just left it all weekend. And so from Thursday pm to Monday am that fridge has run perfectly and without any issues and the battery has lasted easily.
The question is - why the hell did I buy 150w solar panel. Well I’m not sure the heat challenged the fridge and there was no other usage, phones, lights TV etc

So now I’m experimenting to see if the solar on 2/3 panels in the windscreen will give me anything.

This is the parked up scenarios

View attachment 117209

View attachment 117210

View attachment 117211

View attachment 117212

View attachment 117213

View attachment 117214

that looks like a good result.

your fridge running took the leisure battery from 13.0v (1800hrs 20th)

down to 12.0v (1900hrs 23rd)

so three days . . . .

BUT !!


This is not a real scenario.

start opening and closing the fridge, all the time

take cold drinks out,

put warm drinks in, ( to replenish the cold ones)

take milk in/out. ( for tea and coffees)

take cold food out, add other food back in. (bacon, sausage, burgers etc)

Run the LED light from the battery for 4hours per eve . . (if LED lights are running from thbe leisure battery)

Have your USB kit charging stuff all weekend . .

open and close the van doors all weekend.


you will soon find yourself with a very different outcome. . . and possibly a flat battery.

we now run 400W+ mobile solar with 2x compressor fridges + Lithium . . . plus lights and USB chargers etc etc etc , . . and that is self sufficient with good sun with enough capacity for a cloudy day in the middle.

.


so i think your 150W is about right (should give about 9A/Ah max recharge during strong sun)

but have a cloudy day . . . . . and you might come unstuck.


...



so i think you will be fine . . . but do some more real world testing.

do that test again, but simulate the above, keep taking cold stuff out the fridge and replace with warm, run the LED light for some hours, charge up so USB devices etc etc etc


++++


have a quick look over here, when we miss judged the setup and had some not so great weather .... :

https://www.t6forum.com/threads/guide-mobile-solar-panels-how-i-did-it.13225/post-202837

.

 

[James1000]

@Dellmassive - I agree with your scenarios and saw your post. I have tried today to bring the battery back up on solar and failed.

However, some of my real world tests would actually help

I don’t normally use freezer setting so it would have lasted longer

I’m not sure I have ever done 3 days without moving the van = battery charge

I will try those other uses to drain the battery. Food is always the important factor hence my baseline test.

 

[AussieMick]

You may be surprised how much extra you draw from your battery when charging a couple. of phones, lights at night, the fridge running a lot more when you are actually using it.
Using the above scenario I use about 30ah to 40ah per day and 150w solar panel would just cope providing the weather is sunny a fair bit.
One or two days of cloudy weather and you may struggle to put enough back .
Especially if its still warm outside.
If using an agm battery you can only take them down to 50% of capacity regularly for longevity so a 120ah only gives you 60ah or so.
If you are parked in cloudy/ rainy weather a couple of days will soon use available power from your battery unless some decent solar input.
Of course you can use a lithium lifepo4 battery down to 10 percent or so but initial cost is much higher.

 

[James1000]

So could do with some pointers here on my continual test. With the sun making an more improved appearance, out went the solar panel this morning.

When then sun came out in force the meter shot up to 13.4v and ‘Charging’ appeared on the app - all good. Excellent in fact from a battery at 11.8v

I went out at lunchtime to check and in blue skies nothing could get the meter above 13v so the charging graphic did not appear. I checked the voltage at the panel 22.5-23 checked everything else but it would not get me to where it was in the morning? I cannot work it out, I switched off fridge etc just leaving battery to charge and nothing to match the readings in the morning.