Do I need a remote temp sensor?

[BigT]

I've read that remote temperature sensors are a good idea if you want to achieve the most efficient charge from your panel, but what if you're only using your battery for tiny loads, and even then, only occasionally? (dumb question, right?). 

My tiny Transit Connect will never be used for living in, but instead just for the extremely rare weekend getaway for a night or two.  

The only thing I use my under-hood, 75Ah AGM battery for, besides starting the engine, is to run my CPAP machine for 8 +/- hours a night.  
Given how little my CPAP uses, it's likely I'm cycling my battery no more than 4 Ah a night.  

Occasionally, in the summer, I'll run my "Endless Breeze" fan for a few hours, but it too only uses 1 - 3 Amps per hour.  

Given those tiny numbers and the fact that I rarely use the battery for "house loads", it seems unlikely my charge controller is "turning on" and allowing power from the panel to the battery at all.  

When I installed the solar, I didn't realize how little I'd end up using it.  It was also just an experiment to see how things went together.  

It's not a big deal to run a temp sensor, but skipping it this time when I change the location of my charge controller, would make the process a lot easier as I would not have to remove all the plastic panelling from the inside of the van to route the wire to its new spot.

 

[Trebor English]

I have a cheap PWM charge controller that has no connection for a temperature sensor.  I just change the programmable voltage.  

There is a lot about my system that is far from optimum.  Temperature compensation would be better.  Maybe a "real" deep cycle battery would be a good first step.  Meanwhile I'll keep using my velveteen battery, 75 Ah flooded.  

Do you have an infrared thermometer to check the battery temperature?  It surprised me how much hotter one end of the battery was than the other end.

 

[jimindenver]

A remote temp sensor is used to adjust absorb and float voltage when the temperature changes. Higher voltage for colder, lower for hotter. Default setting is at 77 F I believe. So it was a bigger issue for me when my trailer sat in a storage lot at any where from -20 to 105. Now that I follow the weather and the bank is in a temperature controlled trailer the temperature rarely varies.

A voltage sense line so that the controller knows exactly what the banks voltage is has more importance to me.

 

[John61CT]

First off, anything beyond stock vehicle stuff is House loads, but only one batt, not relevant.

I am surprised at your low estimation of AH consumed, must be a much more efficient CPAP than most.

A Watts Up meter will give an objective measure.

Finally, although usually I would recommend temp compensation , you are correct in this case it's besides the point.

I would however suggest a little jumpstarter powerpack kept fully charged if caming off in the boonies.

 

[GotSmart]

You don’t NEED anything. When your battery dies in the future, buy a better one. If you start draining the battery regulary you might need a auxiliary charging source. Right now play it by ear. No need to start throwing money at a problem that does not exist.