Ensuring I am doing the right thing

Vic

Re: Ensuring I am doing the right thing

Hi Rngr,

I did post this previously in this Thread, "Please use the settings recommended by Trojan, at least until you do get the Hydrometer. I do not want to pick, but a few tenths of a volt does make a difference, so, IMHO, your settings are not really that close to the recommendation".

So, Please, Please DO reset the Absob voltage to exactly what is specified by Trojan, 59. 2 volts. Later if you are not using much of your battery's capacity, you might be able to reduce this setting a bit. However, as we move toward Winter, many of us become "Opportunity Charger" types. This is when we try to get as much charge from PV as we can, and then it is OK to jack up the Absorption V a bit more. Of course, this higher V only works when the charger gets into the absorption stage.

Also, in my opinion, the EQ voltage should be temperature Compensated. There is a place in the Classic's Menus to enable that, and believe that you should do that. Some inverters do not compensate EQ voltages, so if the bank temp is very far from the speced temps for the batts (think it is 80 degrees F for Trojan), you might need to temp comp the inverter EQ voltage manually by adjusting the EQ voltage a bit.

And, am certain that you are using the Batt Temp Sensor on the Classics AND on the Inverter as well (?), this is very important.

So please DO increase the Abosorption voltage settings on the inverter and Classics to that recommended by Trojan -- 59.2. Then you might wait for a few days, monitor the SGs, and then decide if the A.sorb time should be changed. The high-ish Vabs needs to be set this high if for no other reason that that is what the mfg says, and also because these batts have fairly high SG electrolyte.

Please rinse your Hydormeter after each measuring session, several times, using distilled water -- this is important.

There is a lot to digest in this Thread, good luck, Vic

Rngr275

Re: Ensuring I am doing the right thing

Vic,
I re-read the owners manual and Trojans web site and there is a a little twist: It says"

Daily Charge= 59.2v
Absorbtion charge for RE-Applications= 56.4-58.8v

So I think the 58.8v I have set for Absorb would be correct for this application? Would you/everyone agree?

vtmaps

Re: Ensuring I am doing the right thing

Rngr275 wrote: »

I re-read the owners manual and Trojans web site and there is a a little twist: It says

Daily Charge= 59.2v
Absorbtion charge for RE-Applications= 56.4-58.8v

So I think the 58.8v I have set for Absorb would be correct for this application? Would you/everyone agree?

I would go with Trojan's recommendation for RE. But, since that is a lower voltage, I would also do a short equalization every week. Many battery manufacturers recommend high voltages for their 'daily' charge, but this is in the context of deeply discharged batteries that need to be fully charged in a hurry (before the next shift). Doing daily high voltages may be hard on a battery that is only discharged 15-20% every day.

Forum member 'Stephendv' has written about some charging profiles for some european RE equipment that uses a daily lower voltage absorb and once a week does a higher voltage finishing charge. It makes sense to me and I might lowering the daily charge voltage on my system (I'm at 29.6 volt daily absorb which would be equivalent to 59.2 on your system).

Another approach that some folks take is to use lower voltages in the summer (when you have more hours of absorb time) and higher voltages in the winter (when there are less hours available).

Bottom line is that long hours of high voltages are bad for the battery.

--vtMaps

Vic

Re: Ensuring I am doing the right thing

Hi Rnge..

Thanks for the added info regarding RE Vabs settings.

There are several ways to increase the SGs of your battery bank. Absorption Time, Voltage, and EQ Time and Voltage.

Increasing the Absorb time would be the first to try. But, if , for example, you do not have enough time in the Solar day to get the charging done, then one can increase the Vabs. The higher V will cause a bit more water to be used, but getting the SGs up to the target value speced by Trojan is important.

Your bank is young. Just get those SGs up to 1.277-ish, and then you can begin tweaking the Absorption time and Voltage, and calibrating the Batt Mon. But, the batteries are not getting fully recharged, and this needs to be remedied as soon as at all possible. Your batteries are a member of your family. They are asking for attention, so please get the SGs up to 1.277-ish NOW. It IS good that you are paying attention, and asking questions now.

Good Luck, Vic

Rngr275

Re: Ensuring I am doing the right thing

Thanks All... I am determined to NOT be one of those who ruin their first set of batteries!

Blackcherry04

Re: Ensuring I am doing the right thing

Rngr275 wrote: »

Thanks All... I am determined to NOT be one of those who ruin their first set of batteries!

You have a lot to learn, half the battle is having good equipment and you have that. Knowing and learning your system and usage will be a part of your life. If you'll spend time now as the season changes you'll learn all the little nuances that make your system successful. There is a huge difference between ending the day with your SOC @ 80% and knowing if you can make it through the night. You'll soon realize that you don't have 50% of your capacity, you only have 30%. You'll know that your Bulk Charge Voltage has to reach 54.5 v or system voltage has to be at least 50.4 v before you can go through the night and if it's not you'll have to do some supplemental charging before bed time ( My system numbers, your will be different ). Then once you learn it, everything will change, being aware of the changes you can stay ahead of it. Training your family members is important also, if they don't help you it makes it twice as hard.

Take your time,if in doubt write it down.

Vic

Re: Ensuring I am doing the right thing

Hi Rngr..

I would crank up the Absorb voltage to 59.2 or so AND increase Absorb time as well, until you can get the SGs up to spec. Then you can quite possibly reset the V a bit lower, but only if you can complete the Absorption stage in the time that you have enough PV input to get into Float. You know your local weather, I do not!

To me, the first 25-50 cycles of the bank increases the CAPACITY of the bank. The SG should get the 1.277 target on most of these cycles. This is the way tha all of the banks that I've had/monitored have been, although, none have been Trojans. But, would be surprised if Trojans behaved differently.

vtmaps, yes the "lower Summer Vabsorb, higher in Winter" is the Opportunity Charge that referred to above. YES, many hours of too high charge V is bad, chronic undercharging is considerably worse. IMHO.

Rngr, it IS very good that you are paying attention to your system/batteries, and asking questions, when the system is young, not when the "lights go out"! Good Luck, Vic