Morningstar SunSaver SS-10-12v Charge Controller 10A 12V

• Constant voltage pulse width modulation (PWM) charging
• Epoxy encapsulated electronics ensure durability and longevity
• Includes a temperature compensation sensor
• Rated Solar Current: 10A @ 12V
• Rated Load Current: 10A @ 12V

This is an update after 5 months of constant use in Baja california. I run a 12volt refer and the lights to a small house.

Testing with a watt meter:

Watt meter between charger and battery. my panels

( 320 year old 50 watt panels) had at least a peak wattage of 130 (9.5 amps) watt on a sunny day, and hit 200 watts on some partly cloudy days. So the unit was pushed to the max, and held up well. Wattage to a fully charged battery was 5-8 watts. There was no heat coming from the unit. Would up my rating 5 stars. Therefore the following review should be changed in spots, but I'll leave it for now.

How Morningstar Sunsaver ss-10 works and the potential flaw.

Assuming temperature 25 degrees C: the controller will put a voltage of 14.4v into the battery. With no load on the system, and sun, a voltmeter will always read 14.4v no matter what state of charge the battery is in. This is just what my battery type wantsconstant voltage. So far great.

But when the battery is fully charged , the float voltage does not go down to around 13.7v. The float voltage is 14.4v. After 2 days of charging, an analog amp meter shows zero current going into the battery. however my 0-25a meter is accurate at best to + 1 amp. So maybe a float voltage of 14.4v is ok? Provided the current is very low. My batteries (expensive) call for a float votage of 13.2v to 13.7v. I'll know more when I get a digital amp meter.

I can't find any specs from Morningstar on how much current is going into a fully charged battery.

It's just sort of dissapointing that I spent the extra money for a name brand, and may have ended up with an inferior product. If I had known the float voltage was 14.4v, I would not have purchased. Especially with no specs on current at the float voltage. If I hadn't modified the mounting holes , I would return it. Now I'm left with the problem of finding out the current myself, and then babysitting the thing so my batteries don't overcharge.

The temperature sensor works well.

Correction. I started out with an 85% charged battery. I do not know what the initial charging battery voltage would be if I had started out with a more discharged battery. Probably would depend on % battery charge and output of solar panels. Float voltage still 14.4v.

Update. I bought a 10 amp controller that looks identical to the HQRP 10a. Was not purchased from amazon. Was 20 bones delivered.

That controller is way way worse than the sunsaver. It starts the day on a fully charged battery and enters an equilization phase. Battery voltage is brought up to

16 plus volts then shut off until voltage goes down to 14.4v. Then the full power of the panels ( 6 amps in my case)is put into the battery until voltage goes to 16 plus again. This went on for an hour until I pulled its plug. Next day same thing. I'm not sure what kind of battery likes this treatment. Not gel and not my AGM. Would be ok for an old car battery you don't care about. So for under 60 bucks the morningstar may be as good as you can get.

I've put a switch on the morningstar and can lower the float voltage to 14.1v. I think I can live with that. Or maybe go back to the nc25a I was using.

I have no use for the load contols on these controllers. I'm not lighting a street lamp. My main use is running a fridge/freezer, that shuts down when batteries are below 12 volts. I would be happy if the manufacture left out the load feature and just spent the savings to make a charger that correctly charged the battery.

Buy Morningstar SunSaver SS-10-12v Charge Controller 10A 12V Now

The Morningstar SunSaver Charge controllers do the job.

My solar system is for a weekend cabin that is mostly used during the summer and autumn.

But be careful in hooking up; I damaged one when I inadvertently shorted a connection.

Another one was damaged when mice built a nest on top of the controller and it overheated.

Read Best Reviews of Morningstar SunSaver SS-10-12v Charge Controller 10A 12V Here

The unit is well engineered,and maufactured.There is no way one could install product wrong.The risk of short circuiting is practically impossible,as there are tall walls between the terminals.It is epoxy encapsulated and therefore waterproof.The backplate is constructed in such a way as to insure ventillation,minimizing heat buildup.I would definetly recommend this unit.

Want Morningstar SunSaver SS-10-12v Charge Controller 10A 12V Discount?

This was the exact replacement for my solar panel controller on my RV.

Have had it for several months and it is working like new.

Save 24% Off

Looks like a high quality product as per specifications. However, the unit I received is defective correctly connected to a perfectly working solar panel there is zero output on both the load and battery connections. Hoping for better luck on the exchange...