Issues can appear with battery levels on the Fusion Mini which can cause the unit to not charge properly.
These issues can manifest where we normally expect them; for example, on a cloudy day but can also happen on very hot and sunny days. Fusion Mini placement can also affect charging capability.
Low/High Ambient Temperatures
The 6000mAh battery supplied by FreeWave in the Fusion Mini will prevent charging when the ambient temperature is below 0°C/32°F or above 40°C/104°F
Lithium batteries should not attempt to be charged below 0°C/32°F as doing so can permanently damage the cells.
Charging above 40°C/104°F can cause the battery to swell.
If your ambient temperatures are below or above the specified temperature, the batteries will not charge.
Direct Sunlight on the Keypad/Enclosure
If the Fusion Mini is oriented away from the correct orientation (solar panel facing south in the northern hemisphere or reverse in the southern hemisphere), direct sunlight on the black keyboard enclosure can cause the NTC thermistor that governs the charging capability to believe that the ambient temperature is above 40°C and therefore stop charging.
No direct sunlight on the solar panel
If the Fusion Mini is not receiving direct sunlight, it will not charge.
This can be caused by Fusion Mini movement especially if the Fusion Mini is not tightly secured to an object. Wind and animals are among the reasons why Fusion Minis move.
If the hex nut was not screwed tightly during installation, it's possible the solar panel may have fallen flat and is no longer on an angle.
The change in seasons may have also had an effect. Buildings and trees that weren't an issue during a summer install may now be causing shading on the Fusion Mini.
Can I tell whether the panel is receiving sunlight without visiting?
The Fusion Mini sends charging telemetry with every sample sent to the portal. This includes the charging voltage, whether the unit is charging, and whether is there any observed fault with charging.
How can I see it?
There are three ways to see charging data.
1. Using the Device Power Performance Graph
In the FreeWave Portal, you can navigate to your list of Fusion Mini's and beside the name of the Mini, you'll see the Device Power Performance graph link.
Clicking in that will bring you to the graph.
By default, you will be shown the graph for Today. Depending on the time of day and the number of messages received, may see a small graph.
You can use the menu at the top right to select between Today and the last 7/15/30 days.
Selecting another time period will extend the graph.
In the above graph there are distinct colors that refer to the following:
- Darker green bars - These are the current battery level in Volts
- Light green sections - These are the period when the battery is charging
- Blue - this is the charge voltage on the panel
When the blue line is above 16.5V, the battery will charge.
NB: If the ambient temperature is above the limit, the battery will not charge despite the graph indicating it is charging.
2. Viewing Individual Messages
The first is to look at individual message contents in the message viewer.
Please see this article on how to view messages in the Portal.
Expand the objects to find the charge circuit telemetry data.
Here you can see the relevant information.
3. Data Export
See this article is how to do a data export.
In the Excel file, find the charge-circuit tab.
This will list the following columns:
- time (in GMT/UTC)
- b-charge (is the battery charging?)
- b-fault (Is there a fault on the charge circuit)
- i-voltage (voltage being supplied to the charge circuit by the panel in mV)
The FreeWave Fusion Mini generally has a lower charging limit of 16500mV. At that level, the charging circuit will supply 20mA to the battery. At that level, it took 30 days to recharge the battery.
At 17000mV, the battery is receiving 200mA.
As you can see below, the panel is never able to supply more than 16,200 volts and as a result, we get a NO for charging.
Conversely, you can see below much higher panel voltages resulting in battery charge.
What does it mean?
Low panel voltages
If you're charge-circuit voltages are below 16500 during the daytime, it either indicates it's quite cloudy or the panel is not facing the right direction.
In the winter months, the panel needs to face the south (for the northern hemisphere) and the north (for the southern hemisphere). During winter, if the panel is facing the wrong way and it's sunny, the panel may be in shade and not charging.
You also need to look at Fusion Mini placement. Has it moved due to wind or animal, or has someone moved it?? Has the hex nuts become loose and has the panel fallen to horizontal?
Also, if you are in a dusty environment, dust can cover the panel and reduce its effectiveness even on sunny days.
High panel voltages
If you have high panel voltages and the ambient temperature is high, direct sunlight could be heating the plastic enclosure and causing the battery circuit to think the temp is over 40. This will shut down charging and have a NO on the charge column.
There of course could be other issues with the panel or other components. Please contact FreeWave Support.