Recommend a 100 watt Solar Setup for my C-22

[Carl Wonderful]

All good stuff to know. Much appreciated.

Can anyone recommend a battery (deep cycle I guess would be my best bet to start with?) for my setup? I don't even know where to start there.

 

[jssailem]

If you can find one, I would look for an Aerial lift or floor sweeper battery.
I found mine at Dyno Batteries of Seattle. They are 135amp hours, 12V, only 65 pounds, and fit a group 30 space.

Here is the link.

Dyno Battery - Premium Quality Battery Manufacturing - Made in the USA

 

[Project_Mayhem]

The priority switch is either 90/10 or 50/50. They say " If one battery bank reaches full charge before the other, more charge current will be diverted to the lower state of-charge battery." My question here is they say "more charge current will be diverted". It doesn't say 100% of the charge will go to the other battery as they do when only one battery is connected, but I assume it does.

There's only one place it can go if there's only one battery. I'm guessing that this unit will prioritize how much time it sends power to each battery based on that switch. Will that time be wasted on a battery that's not present? Only through testing or by contacting the manufacturer will one find out.

@Carl Wonderful Take some pics and if you do buy the SunSaver, see if there's any voltage on the disconnected battery terminals

 

[Richard19068]

There's only one place it can go if there's only one battery. I'm guessing that this unit will prioritize how much time it sends power to each battery based on that switch. Will that time be wasted on a battery that's not present? Only through testing or by contacting the manufacturer will one find out.

The switches prioritize batteries based on state of charge, not time.

It is clear that if only one battery is connected it gets 100%.

It is not quite clear that if two batteries are connected that the undercharged battery gets 100% of the current when the other battery is full. They say "more" rather than "100%".

I'm probably splitting hairs with that question.

From the manual:

"The SunSaver Duo can charge just 1 battery connected to either the Battery #1 or Battery #2 connections. If Battery #1 or Battery #2 is missing, the remaining battery will be charged with 100% of available power regardless of the charging priority setting."

"The 90% / 10% priority setting allows Battery #1 to receive 90% of available charging current, while Battery #2 receives 10% of charging current. This setting is ideal for RV and boat systems where a “house” bank requires most of the available charge current and a separate engine starter battery requires only a “trickle charge” to remain topped-off. When Battery #1 reaches full charge, more charge current will be diverted to Battery #2 as needed.
The 50% / 50% priority setting splits available charge current equally between two battery banks. This priority setting is ideal for systems with two equal-sized battery banks that require simultaneous charging. If one battery bank reaches full charge before the other, more charge current will be diverted to the lower state of-charge battery."

 

[dlochner]

This priority setting is ideal for systems with two equal-sized battery banks that require simultaneous charging. If one battery bank reaches full charge before the other, more charge current will be diverted to the lower state of-charge battery."

This is Ohm's Law in action. As the SOC increases so does the internal resistance of the battery. In a parallel circuit more current will always flow through the side with the lower resistance and a small amount will go through the remaining side. There is nothing magical about this and there is a formula for calculating the amount of current flowing through each side of the parallel circuit.

 

[Richard19068]

This is Ohm's Law in action. As the SOC increases so does the internal resistance of the battery. In a parallel circuit more current will always flow through the side with the lower resistance and a small amount will go through the remaining side. There is nothing magical about this and there is a formula for calculating the amount of current flowing through each side of the parallel circuit.

I'm not much on electrical theory. Thanks for the lesson.

 

[Project_Mayhem]

The switches prioritize batteries based on state of charge, not time.

Absolutely. PWM applies full voltage to a load based on desired duty cycles, AKA time. That duty cycle would roughly translate to a controlled amount of amperage going into a battery. I'm not sure what method is being used to reduce the voltage from the panels however.

"The SunSaver Duo can charge just 1 battery connected to either the Battery #1 or Battery #2 connections. If Battery #1 or Battery #2 is missing, the remaining battery will be charged with 100% of available power regardless of the charging priority setting."

Well there's our confirmation that it is designed to run with one battery. I must've missed that in the manual.