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I may need closely matched Marine batteries. I can only get around 12 hours powering a refrigerator.

den19420

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May 16, 2022
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I am running 2 marine (flooded) batteries. Both are about 100 AH but they are different manufacturers and slightly different AH capacities.
I have measured 2.5 amps when the compressor comes on, and I have read that these compressors only run about 30% of the time. Battery experts I had access to before I retired were very keen on matching cells and/or batteries because a bad device can dork up a pack or a system. I notice that my frig shuts off when I hit 11.5V. I think I'll take one battery out of the circuit and see if I still get 12 hrs.

The other system component I'm not sure about is the solar voltage regulator. It doesn't even list the manufacturer and they typically sell for $40 and for the life of me I can't get any useful information on settings or operation. What I get on Utube and from my source suggests that neither authority has a clear idea of what the regulator settings can accomplish. I hear a lot that if I run the battery capacity below 50% they will eventually fail to recover.

If anything I describe suggests I may have a problem I"d appreciate help.
Thanks
 
It sounds like the real problem is you do not have enough solar or whatever source for power. When the batteries are driven down to 11.5V you are killing them. Refrigerators really need a complex control to avoid problems. Nobody makes these controls. The fallback is just bigger and bigger batteries. I use only a single car battery to run my fridge and it never drops below 12.5 volts. Rain, clouds, nothing keeps it from working.
 
Please itemize the components that you have for your system. When you mention the "solar voltage regulator" are you referring to the charge controller? Can you take pictures? As EPV mentions, it sounds like you are draining your system dry. You have the batteries connected to an inverter to power the frig? Is this a 12V system? Let's assume you have a refrigerator that consumes at least 1000Wh of power over 24hours. And the inverter itself is also consuming power, say 750Wh over 24hr. If your total battery is 200Ah X 12V = 2400Wh, then you are guarrantied to drain it past 50% each and every day.
 
Please itemize the components that you have for your system. When you mention the "solar voltage regulator" are you referring to the charge controller?



see the attachment. It is a schematic of the system. This is all I got from the seller. It states what the features are but nothing about what settings should be.

Can you take pictures?




As EPV mentions, it sounds like you are draining your system dry. You have the batteries connected to an inverter to power the frig?



The Battery receives charge from the panel through the Voltage Regulator (attachment) . I keep a monitor on the output of the solar panel and the range is 22 – 19VDC depending upon cloud conditions. The battery is connected to the output of the Voltage Reg. The battery connects to a 1kw inverter which delivers 120VAC to the refrig. I keep a meter on the Battery and it hovers between 12.5V and 11.5V. At about 11.5 the refrigerator shuts down.



Is this a 12V system? The Voltage Reg takes 12V from the Battery to operate (attachment). The same battery finances the Inverter.




Let's assume you have a refrigerator that consumes at least 1000Wh of power over 24hours. And the inverter itself is also consuming power, say 750Wh over 24hr. If your total battery is 200Ah X 12V = 2400Wh, then you are guarrantied to drain it past 50% each and every day.



This is good. I was getting thrown by the 50% depth of discharge. I was assuming my two 100 AH batteries has an operating capacity of 50 AH. To complicate this further I have no corolation between 50% depth of discharge and battery voltage. 11.5V cut off was recurring so I assumed that shut off the inverter, and I was not calculating the inverter into the power-loss calc. I have only run them down 3 times sofar. Perhaps they can be rehabilitated.



More batteries or less Period of Performance seem to be a solution. Also, do you think my Voltage Regulator (attached) can be set to shut off before I hit 50% dept of discharge? If I haven’t wrecked these batteries It might protect the next lot



This has been very helpful
 

Attachments

  • solarchargecontrollerpdf.pdf
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OK, it appears that your controller is a generic PMW controller. Not the best choice. You mention nothing about your solar panels, or your inverter, so not much advice can be given yet.

Look on the back of your solar panel(s) and you should see a specifications sheet. It should tell you the watts, Vmp, Voc, Imp, and Isc. Please give us those numbers. Also specify the make/model of your inverter.

Are you measuring the voltage with the meter in daytime, while the battery should be charging, or after sunset? A reading of 12.5V concerns me. During the day, with incoming solar power, you should be seeing 13-14V, not 12.5? The 19-22V readings on the panel sounds like you are reading the voltage while disconnected, so you are measuring the Voc. Is that correct?

With a Voc of at least 19V, I would expect a fully-charged lead-acid battery to reach ~14.4V. If you never see past 12.5V, this suggest to me that your panel(s) is too small. Assuming you are getting ~5 sunhours per day this time of year, and your equipment is drawing >1750Wh, then you would need 1750Wh/5sh = 350W of panels just to break even. That would be four 100W 12V panels. What do you have in place?

My suggestion for right now is to shut off the refrigerator and the inverter, and try to get the batteries are fully charged as you can. If you are not seeing ~14.4V around noon or early afternoon with everything off, then your solar is really inadequate. Let's hope that your batteries haven't already been damaged.
 
find below the link which identifies the solar system I purchased. It includes the panel, and voltage regulator specs. I bought the inverter from a different source.

This is a UPS, so I wanted power for 24 hours to keep my refrigerator/freezer going when utility power goes off. Regardless of need, I will keep the solar going 24/7 to keep the battery pack topped in the event power conks out. My assumption is that I will only have battery power during daylight hours, or 1/2 of the 24 hour timeline. I'm basically testing two 100am marine batteries to set a base line. I learn what I can accomplish until the batteries fail. When I figure out my limitations, I then either add solar current with another panel or storage power with one or more batteries. This is a sliding concept.

Inverter https://mail.google.com/mail/u/0/#s...kbLXSRbNSnLbdwqnkqhbzKnxLwzjtZCfBxVvJZgRKphVQ

Solar Panel and Voltage Regulator

The guys that sold the panel were a pain. I got the panel without MC4 connectors and the Voltage Regulator was not in the box. It was sent later. They had no documentation or ideas what I needed.
I had nothing but problems because they had no idea what they were selling. The package was inexpensive and I figured I'd treat this like "training wheels" on a bike.

In contrast I like the Inverter. It seems to be doing well so long as I keep the load within reason.

Any thoughts you have would be appreciated.

Denny
 
None of your links work. This is what comes up looking for the inverter....
1655867875888.png


This is what I see clicking on the panel link.
1655867949935.png

Why don't you actually look at the stuff you bought and just read of the label information.

Please try to make more effort yourself solving your problems then I am.
 
Keep in mind that the inverter just sitting there will consume power. I saw one video and in his refrigerator setup the inverter running at idle consumed 1/3 of the power of the entire system.
 
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