Is it right that my solar reading is 1 watt?

PaulC70

PaulC70

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Just fitted the Fogstar 300ah and the victon mppt 100/20 and had a look on the app. Now, am I right in saying the 1w at the top is just because it's in absorption mode?
IMG_3726 copy.jpg


Also, sorry for the ignorance, on this screen near the bottom it says temperatur compensation is disabled? Anyone know if it should or should not be like that?

IMG_3727 copy.jpg


Any help gratefully recieved.
 
I think that's the output figure.
 
Most have the 'load' set to off. It is more for a situation like a traffic light with the panel on a pole. The 'solar' shows the voltage the panel is making, and of course 'batt' is the battery voltage. There needs to be enough sun to raise the solar voltage several volts higher than the battery for it to charge.
Your 'float voltage is way too high. Try 13.8v or even 13.5v.
 
As it is unusual to use the 'load' output it may be worth looking at the controller to see if there is a wire connected to that terminal. Uf there is you need to find out what it us driving.
 
chesterfield hooligan said:
Isn't the battery full and the 1w is just a float.
Click to expand...

I thought this but it's in absorption mode currently, but the battery is fully charged so this why Im fairly sure it's ok.

68c said:
Most have the 'load' set to off. It is more for a situation like a traffic light with the panel on a pole. The 'solar' shows the voltage the panel is making, and of course 'batt' is the battery voltage. There needs to be enough sun to raise the solar voltage several volts higher than the battery for it to charge.
Your 'float voltage is way too high. Try 13.8v or even 13.5v.
Click to expand...
OK, makes sense i think. I'll readjust the float voltage too now.
 
68c said:
As it is unusual to use the 'load' output it may be worth looking at the controller to see if there is a wire connected to that terminal. Uf there is you need to find out what it us driving.
Click to expand...
The load output hasn't got anything connected to it at all, it's literally panel in then battery out.
 
It looks like your battery is fully charged at 14.4volts. As your float is also set at 14.4v it never goes to float so continues to display absorbtion. Try reducing the float voltage.

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68c said:
As it is unusual to use the 'load' output it may be worth looking at the controller to see if there is a wire connected to that terminal. Uf there is you need to find out what it us driving.
Click to expand...
I use the load output functionality to switch my fridge over to 12v when there is surplus solar, more often than not my batteries are full by 1100 as I have a large solar array and 960ah of lithium 👍
 
To explain a little further. Your controller tries to charge the battery fully at 14.4volts. After a while the battery will not accept any more ( or very little) current. The controller detects this reduced current flow and switches to float which should not be as high as 14.4volt. This is to protect the battery from sitting for a long time at the higher voltage which may then cause water loss and then failure. As you have set the float so high the controller will keep trying to flip between absortion and float. Reduce your float voltage.
 
PaulC70 said:
on this screen near the bottom it says temperatur compensation is disabled? Anyone know if it should or should not be like that?
Click to expand...
It's possible to get a temperature sensor and attach it to the battery. The solar controller will use this temperature to accurately adjust the charging voltage and current to optimise the battery charging. If there is no temperature sensor fitted, it just uses the temperature of the solar controller, and the Temperature Compensation setting should be disabled. So I imagine this setting is correct if you have no sensor fitted.

However I think fitting a temperature sensor for a lithium battery is a good idea. Charging should be cut off if the temperature falls to zero or below, and a temperature sensor gives it the information to do this. With Victron stuff there are several ways to get the temperature information, and there might be something fitted already that can do this. For example a SmartShunt, Smart Battery Sense or BMV monitor.
 
Looks like the battery BMS may have turned off charging as its fully charged.
The voltage settings are too high.
I would reduce the charged voltage to 14.1v and float to 13.8v.

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Of course my above comments apply to lead acid batts. Should have read the first post better.🫣
 
Mine goes up if the batteries are under load or the battery is low on power and is charging (bulk). If the batteries are full (float) and not being used then the solar registers a very low wattage whatever the sunshine. (I think - not had this controller long so not used it in full sunlight yet)
 
Put a load on the battery equal to the maximum amperage of the controller and you will get an idea of the maximum harvesting possible at that specific time.
Impossible to judge if there is a problem or anomoly when the battery is full or thereabouts.
 
Hoovie said:
Put a load on the battery equal to the maximum amperage of the controller and you will get an idea of the maximum harvesting possible at that specific time.
Impossible to judge if there is a problem or anomoly when the battery is full or thereabouts.
Click to expand...

I don't know what to connect to the load side to be honest, not very good with these things.

ChrisL said:
You can connect a temperature sensor to a smart shunt and it can be set up to pass that data to your solar controller to optimise charging depending on battery temperature.

Temperature Sensors [Victron Energy]

www.victronenergy.com www.victronenergy.com
Click to expand...
So, that means fitting a smart shunt AND temp sensor which sounds a bit beyond my means.

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PaulC70 said:
I don't know what to connect to the load side to be honest, not very good with these things.


So, that means fitting a smart shunt AND temp sensor which sounds a bit beyond my means.
Click to expand...
The victron smart sense devices couldn't be easier. A wire to battery plus, another to minus then peel off the backing and stick it to the battery.
 
PaulC70 said:
I don't know what to connect to the load side to be honest, not very good with these things.


So, that means fitting a smart shunt AND temp sensor which sounds a bit beyond my means.
Click to expand...
A Smart shunt can be had for a little over £100 and the temp sensor is about £25, if you don't require amps in and out and state of charge the smart battery sense will show battery voltage and pass the temperature to the solar controller for around £35.
 
The load terminals are used in other applications, like solar-powered road signs, night lighting, CCTV cameras etc. However in a motorhome the load terminals are almost always ignored, although they are used occasionally. Motorhome habitation loads like lights, water pump etc are always wired so that they work from the leisure battery. The solar controller just provides charge for the leisure battery.
monzer said:
The victron smart sense devices couldn't be easier. A wire to battery plus, another to minus then peel off the backing and stick it to the battery.
Click to expand...
Another thing about the Victron Smart Battery Sense is that it communicates the battery voltage and temperature data by Bluetooth to the MPPT, so no wire is required for that. The Smart Battery Sense is the one to use if you only need voltage and temperature data. The MPPT itself measures the amps that it is sending to the battery.

If you want a full battery monitor that does all this and also measures the amps and keeps a count of the amp-hours (Ah) into and out of the battery then you can fit a SmartShunt. It's a bit more work to install it, because it needs to be fitted on the battery negative terminal. However you may find that with a simpler Smart Battery Sense and the Fogstar BMS App you have quite enough information.
 
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