I started from knowing nothing about batteries and charging. I read, studied, researched and learned what the battery manufacturers want you to do to maintain their batteries. Yes, there is "how long the battery lasts" but there is also how much charge you get on any given day when you go off the grid. As the battery dies, that time gets shorter and shorter. What is really getting shorter and shorter is the amp hours before you hit the 50% mark where you are supposed to stop using the battery, or charge it back up. If the battery is dying, then even a good solar system and good charger can only do so much because the battery itself is physically damaged.
So I am not looking at "a good bottle of wine", I am looking at buying and maintaining a system such that when I do get off the grid, it gives me the power I need.
When a battery is not fully charged, again according to the battery manufacturers, it begins to damage the battery. So if the system routinely charges to 80% then before long you permanently lose 20% of the battery's ability to store power. As you no doubt know and agree, if you use more than 50% OF THE ORIGINAL charge storage, then you begin to damage the entire battery, effectively killing the entire thing.
So... charger X only charges the battery to 80% of the "full" level. What is available for you to use when off the grid? 30% of the original "full charge". So you go buy a 120 amp hour deep cell. When you first start using the battery you get about 60 amp hours before you need to recharge. Or looked at from the flip side, you NEED TO recharge when the battery has 60 AH left.
Your charger X only ever charges it to the 80% point so it permanently kills 20% of the capability. So after a year or so, the battery only holds 120 * .8 amp hours or about 96 amp hours. You can still only draw it down to 60 amp hours so you now have 36 amp hours available before you need to recharge.
You have gone from 60 AH available to 36 AH available. Except YOU don't know this. You continue to pull 60 AH out because that is the magic number right? NOPE, not right, you need to RECHARGE when the battery still has 60 AH, the 1/2 way point of the ORIGINAL FULL CHARGE.
So now you are drawing out 60 AH because you mistakenly believe that is what you have available and you are now drawing the battery down below the magic 1/2 way point and you are doing more damage to the battery.
In the end, in YOUR case, YOU may not ever know you are doing this. The battery dies eventually and you go get a new one. You think your battery lived a full and productive life and after all, it's really just a bottle of wine a year right? Yep, right. You kill your battery and replace it.
I have news though, the battery would last a LONG time if it is treated right, and you could get 60 AH for that entire time without damaging the battery.
Carol, I am not saying that you shouldn't just view it your way, replace the battery every once in a while and not worry about the cost. It works for you, you get the current you need and when you don't you go buy a new battery. Great solution for you. But I want to get 120 AH year after year. NOT 120 AH this year, 90 next year, 60 the year after, 30 the year after, replace the battery. That works for you because you never needed more than 30 anyway.
The PD charger, WITHOUT the charge wizard, is a bad solution. It does NOT correctly charge the batteries. THEY TELL YOU THAT, but most people don't read or understand what they are being told. They say they guarantee 13.5 V "nominal" to charge your battery. That's GREAT right?
The battery manufacturer of flooded cell batteries say it takes 14.8 volts to correctly charge a battery to the FULL state. So... PD figures out that their own systems are damaging their clients batteries, and with much fanfare they create a new wonderful "Charge wizard" which they trademark the name, and they trumpet how with the charge wizard, damage to your batteries is eliminated.
RIGHT? Remember that? Except that they are still selling the original unit without the charge wizard to THOUSANDS of people, every year. The original unit guarantees 13.5V 'nominal' charge voltage! The original unit is GUARANTEED to damage your batteries!!! And they KNOW THAT!!!
Pardon me if I am not impressed that, if you happen to discover that their charger is killing your batteries, and if you happen to discover that you can buy a wizard from them to stop it from killing your batteries, and you actually pay to buy it and get it installed, THEN the charger that you paid for will not (overtly) kill your battery.
Yes, I am irritated. I am irritated that PD knows that their original charger without the wizard is killing batteries and continues to sell it to the unsuspecting public. I am irritated that they then tell us poor suckers that if we will just buy an additional "charge wizard" from them, then they will no longer kill our batteries. And I am irritated that we, the poor suckers buying this stuff think that whole situation is OK.
I don't think it is OK. I think they should just wrap the damned charge wizard in a new model, STOP SELLING the old model, and trumpet how their charger is so much better than the competition (or something).
Understand that even WITH the charge wizard, they only charge the battery to 14.4 volts, NOT 14.8 volts but hey, nobody out here gives a rat's patuty (to quote Bob) about any of this.
Furthermore, charging a battery requires HOLDING the bulk charge voltage until the CURRENT pushed into the battery starts to drop. But guess what the "Charge Wizard" does. TIMES it. Yep, after X minutes it drops to the second level. WRONG ANSWER!!! So if my battery is LARGER than yours, them MY battery is REALLY badly charged, even with the "Charge Wizard".
So they still aren't getting it right, but in the end, who cares. The batteries are lasting longer anyway. That really is a good thing.
Have you been to Sears for any automotive work? They show the "Good", "Better" and "Best". PD has moved from "Abysmal" to "Better" in one fell swoop. Bravo for them. EXCEPT that we have to somehow stumble on the fact that without the wizard they are ACTIVELY KILLING our batteries and then we have to do something about it.
I am NOT impressed.
And yes, since I already have the PD unit that apparently accepts the "Charge Wizard" I may go get one, because, after all, "Abysmal" to "Better" is a giant leap. Except that I have a larger battery so their TIMED method doesn't work well for my batteries even with the "Wizard"
Or maybe I'll just go research and find an after market widget that actually CORRECTLY charges the battery, multi-stage, to 14.EIGHT volts, watching the CURRENT consumption to decide when to change stages, and install that. Disconnect the crappy thing that PD sold
me and be done with it.
Carol, I actually studied the issues. My educated opinion is that PD is not something that I would go buy if I had a choice. I said that pretty much in my original reply. I absolutely mean it.