24/7 DC solar setup

I am setting up a wireless fuel sensor and need to be able to power it. I plan on using power but I am having problems with understanding how to set it up properly.
The total system runs at 15 Watts @24VDC. and it has to be running 24/7. My problem is the wiring for the whole setup. it seems that I can wire my solar panel to my charger, and from there I can wire the charger to the battery and just hook up my load to the battery directly.
My boss believes that some form of second controller is required to decide if the power comes from the solar panel or the battery and I honestly just can not figure out how to set this thing up. I have been looking for answers for 2 days.
I am not sure if that is correct or not. If you know how to set this up I would greatly appreciate the help.
The total system runs at 15 Watts @24VDC. and it has to be running 24/7. My problem is the wiring for the whole setup. it seems that I can wire my solar panel to my charger, and from there I can wire the charger to the battery and just hook up my load to the battery directly.
My boss believes that some form of second controller is required to decide if the power comes from the solar panel or the battery and I honestly just can not figure out how to set this thing up. I have been looking for answers for 2 days.
I am not sure if that is correct or not. If you know how to set this up I would greatly appreciate the help.
Comments
Hook up the load to the battery and the solar panel(s) to the charge controller and from the charge controller to the batteries.
Calculate the load based on the 15 watts x 24 hours or about 360 watt hours. It would be good to measure the load, may be more or less than the rating based on the amount of lift. 15 watts sounds pretty small. I have a tiny water pump that draws 40 watts.
- Assorted other systems, pieces and to many panels in the closet to not do more projects.
The full range of DC Voltage on an off grid/flooded cell lead acid battery bank can easily range form 21.0 VDC ("dead" battery) to ~30-32 VDC (charging/float charging/very cold battery bank).
If your electronics do not "like" that wide of voltage range... Then having a small buck/boost DC to DC converter to output closer to 24.0 VDC over time/temperature/state of charge--That may be helpful.
https://www.amazon.com/s?k=buck+boost+dc+to+dc+converter&ref=nb_sb_noss
Note: For 24 VDC battery bus to 24 VDC electronics, you need a buck/boost type converter. "Buck" mode drops from input to output. "Boost" mode increases voltage from input to output.
If you, for example, had a 48 VDC bank and a 24 VDC load--Then you would only need a "buck mode" type converter.
-Bill
|| Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
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