Corrective Equalization for newly installed Rolls batteries

Blackcherry04

Re: Corrective Equalization for newly installed Rolls batteries

Back in the day, Heart Interface had a 8 hour fixed time and Trace had a 4 hour time for EQ. Both would do more damage than they corrected. Those kind of times can boil off a lot of water and cause some high temperatures. I'v never been a fan of Automatic EQ either, people forget about it and do not service their batteries and run into trouble.

I once had customer with a runaway and the batteries actually burned a imprint into a sheet of plywood. They never caught fire , but I don't know why. They had been unattended for 4 months in the off season, on grid.

NorthGuy

Re: Corrective Equalization for newly installed Rolls batteries

Cariboocoot wrote: »

One thing Xantrex got right is limiting EQ to an hour.

I wouldn't agree with that. When someone does an equalization, there must be a reason for that. Longer equalizations often may be required. When you press the equalization button, XW goes through one hour and stops. This creates an illusion that the goal is accomplished, while, in fact, you may be far from it. That's exactly what happened to me when I first used it!

If you do know that you need more than one hour, you cannot use the built-in function, and need to spend quite some time going through their menus to trick it into doing what you want. In the process, you have to alter operating settings. If you forget to put original settings back, a disaster can easily happen.

Cariboocoot

Re: Corrective Equalization for newly installed Rolls batteries

You need longer EQ: you do it again. And again if necessary. Until the improvement in SG stops. It may be tedious, but it's better.

Some people want a button on the inverter that says "FIX BATTERIES" so they don't have to make any effort at all.

It would be ideal if there were individual cell management (BMS) for lead-acid batteries just as with the Lithium ones. Then only those cells that needed the EQ would get it, and save stressing the ones that don't. But such is too complex to be practical.

NorthGuy

Re: Corrective Equalization for newly installed Rolls batteries

Cariboocoot wrote: »

You need longer EQ: you do it again. And again if necessary. Until the improvement in SG stops. It may be tedious, but it's better.

Nothing is that simple in Xantrex. It wants to make sure the batteries are fully charged before you do equalization. So, when you press the EQ button, it runs the full cycle first. When you do it again (by pressing the EQ button again), it will go through the full charge cycle again, then do equalization. If absorption is set for a fixed time, say 3 hours, every time you press the EQ button you'll receive short bulk, then 3 hours of absorption, then one hour of equalization. Perhaps, not what you wanted. To accomplish relatively continuous equalization, you would need to change absorption duration to 1 minute, so that your charge cycle is short. Then you forget to change it back and, just by coincidence, you get a cloudy month (or two), during which time your batteries go without absorptions, and die ...

Cariboocoot wrote: »

Some people want a button on the inverter that says "FIX BATTERIES" so they don't have to make any effort at all.

Exactly. The "EQ" button on Xantrex is designed just for that sort of people. Press it, it'll fix your batteries. If not, press it again ...:p

Cariboocoot

Re: Corrective Equalization for newly installed Rolls batteries

NorthGuy wrote: »

Nothing is that simple in Xantrex. It wants to make sure the batteries are fully charged before you do equalization. So, when you press the EQ button, it runs the full cycle first. When you do it again (by pressing the EQ button again), it will go through the full charge cycle again, then do equalization. If absorption is set for a fixed time, say 3 hours, every time you press the EQ button you'll receive short bulk, then 3 hours of absorption, then one hour of equalization. Perhaps, not what you wanted. To accomplish relatively continuous equalization, you would need to change absorption duration to 1 minute, so that your charge cycle is short. Then you forget to change it back and, just by coincidence, you get a cloudy month (or two), during which time your batteries go without absorptions, and die ...

Which is what's wrong with the Xantrex; they haven't got the Absorb function right and you should be able to repeat EQ as needed (even though batteries should be fully charged before EQ, it's redundant to do Absorb again if the charge cycling hasn't dropped back to Bulk indicating the start of a new cycle).

On the whole, Outback does it better.

NorthGuy

Re: Corrective Equalization for newly installed Rolls batteries

Cariboocoot wrote: »

Which is what's wrong with the Xantrex; they haven't got the Absorb function right and you should be able to repeat EQ as needed (even though batteries should be fully charged before EQ, it's redundant to do Absorb again if the charge cycling hasn't dropped back to Bulk indicating the start of a new cycle).

It probably would've figured that it doesn't need to go through the full cycle every time the EQ button is pressed if it was in "Bulk-Absorb-Float" mode as opposed to "Bulk-Absorb-No Float", but I haven't tried this.

tonygcan

Re: Corrective Equalization for newly installed Rolls batteries

2 weeks after I was able to raise my SG readings in my batteries I went ahead and measured the SG keels again. I found that when my XWCC went into float mode most of my batteries read 2.170-2.180, some read 2.160 - 2.170 and four of my cells had a reading of 2.150 - 2.165.

Rolls states that my batteries should have a reading of 2.180.

I'm wondering if my XWCC is not charging sufficiently?

I have set my XWCC to custom battieries, 450 AH capacity, 48 volt system. My bulk voltage is at 59 volts, my absorb is at 60 volts, equalize is at 62 volts. Absorb time is at 270 minutes and float is at 56 volts.

Do I have my amounts right or should I be tweaking my values?

Thanks.

Cariboocoot

Re: Corrective Equalization for newly installed Rolls batteries

Tweak time.
Surrettes actually want higher than normal Voltage.
One of the problems is that the Voltage readings themselves may not be accurate.

You've got some lagging cells; see if you can run additional EQ cycles and improve them.

NorthGuy

Re: Corrective Equalization for newly installed Rolls batteries

tonygcan wrote: »

2 weeks after I was able to raise my SG readings in my batteries I went ahead and measured the SG keels again. I found that when my XWCC went into float mode most of my batteries read 2.170-2.180, some read 2.160 - 2.170 and four of my cells had a reading of 2.150 - 2.165.

It is something wrong with these numbers. Do you mean 1.170-1.180 or 1.270-1.280?

Cariboocoot

Re: Corrective Equalization for newly installed Rolls batteries

Good spot. The creeping dyslexia strikes again; I automatically read "1.270" instead of "2.170" for all.
I should probably be worried about that.

niel

Re: Corrective Equalization for newly installed Rolls batteries

the higher numbers in the 2+ range look like per cell voltages and not specific gravity.

coot,
what should you be worried about, the dyslexia or the numbers?:D

Cariboocoot

Re: Corrective Equalization for newly installed Rolls batteries

niel wrote: »

coot,
what should you be worried about, the dyslexia or the numbers?:D

Both!
It's bad enough when you read your own stuff and see what you think you wrote instead of what's really there.

Vic

Re: Corrective Equalization for newly installed Rolls batteries

Cariboocoot wrote: »

Surrettes actually want higher than normal Voltage.

Marc, I do not want to pick at this, but, NONE of the Surrettes here -- three banks of 4000 and 5000 series FLAs need anything but Vabs in the lower middle of that recommended by Surrette. In my case, nominally 58.1-58.3 volts compensated for temperature. Of course, the exception is when one is charging from PV. In this case due to short days, a too-small PV array for battery capacity, etc, many of us need to jack up the Vabs to recharge batteries from the power available. BUT these Surrettes should not require Vabs above that speced in the Surrette Battery Manual or Solar Battery Manual:

http://support.rollsbattery.com/solution/categories/688/folders/10484

The Manual has been recommending target SG readings of 1.255 - 1.275. Previously they recommended a target of 1.265

The only member here that seemed to need a HIGH Vabs is Chris Olson, who appeared to need an EQ style Vabs during full recharges. He reported that this was because his FLA Marine batts used a Lead-Calcium grid. This is not typical or even recommend construction for RE off grid use, IMHO. Have been a bit concerned that this style Vabs will become part of the standard recommendation for those using Surrette Solar batteries.

Many other manufacturesr DO want higher Absorb voltages, particularly for batteries with highish SG electrolyte -- on the order of 1.277 - 1.280 or so.

And tonygcan PLEASE NOTE, unless you have information from a direct communication from Surrette directly to you, the target SG that you are aiming for with Surrette FLAs is; 1.265. The 1.280 on the Surrette Data Sheet is a way to make the Capacity appear a bit higher (5%) than it really with the electrolyte that is almost always shipped in their Solar batteries.

I assume that your 450 AH 6 V Surrettes are S-600s ??

For now, the 60 volt Absorption voltage is fine until the battery SGs come into the target range.
Would recommend that you set the Bulk voltage the same as the Absorb voltage.

IN addition, your Float voltage should be LOWERED to the Surrette-recommended 52.6 V, at least when your batteries start to become fully charged.

Since you seem to be still having problems with LOW SGs, it might be good for you to increase the EQ voltage somewhat, perhaps 63 V until you get the recommended SGs, then it can be returned to 62-ish V.

Have these batteries been using any water recently ?? ?

Harping is over for now. Good Luck, Vic

westbranch

Re: Corrective Equalization for newly installed Rolls batteries

Tony, you did not mention if you were BULK charging with the Genset or not?? and the time it took.
What were your SoC's before charging, especially those lower cells?

tonygcan

Re: Corrective Equalization for newly installed Rolls batteries

Apologies, yes I meant 1.255 -1.280. Yes Vic, I believe my batteries are the series 600.
Thank you for the suggestions on the values for my settings. I will make the necessary adjustments.
WB - I use the grid to charge the batteries when their isn't enough sun. Regarding the SoC, I can't say for sure but the lower cells had an SG of 1.45 - 1.50 and the good cells were at 1.565 or more.

When equalizing with XW 4548 hibrid inverter I can only do an equalization for an hour and then I have to press the equalization button again. The XW will go through a whole cycle again before equalizing. I'm wondering if this could be the reason why I can't get th lower cells to improve? Should the equalization run continuously in order for the cells to shed off its plaque? Should I trick the inverter to float at 62 volts when equalizing and monitor the temp while doing so? Thanks.

Also, I only filled up because I had done corrective EQ.

Cariboocoot

Re: Corrective Equalization for newly installed Rolls batteries

My preferred method is to EQ for an hour and repeat as necessary until things stop improving. There's some problem with getting Brand 'X' equipment to do this, though.

I think some others have 'fooled' Xantrex into longer EQ by upping the Float Voltage and then keeping a close eye on everything - and remembering to dial it back down afterwards.

NorthGuy

Re: Corrective Equalization for newly installed Rolls batteries

tonygcan wrote: »

Regarding the SoC, I can't say for sure but the lower cells had an SG of 1.45 - 1.50

I would take that to mean 1.245-1.250

tonygcan wrote: »

and the good cells were at 1.565 or more.

1.265 perhaps?

tonygcan wrote: »

When equalizing with XW 4548 hibrid inverter I can only do an equalization for an hour and then I have to press the equalization button again. The XW will go through a whole cycle again before equalizing. I'm wondering if this could be the reason why I can't get th lower cells to improve? Should the equalization run continuously in order for the cells to shed off its plaque? Should I trick the inverter to float at 62 volts when equalizing and monitor the temp while doing so? Thanks.

I would set the Float to 62 to let it run. I don't think that keep pressing the EQ button every hour would be somehow worse.

Vic

Re: Corrective Equalization for newly installed Rolls batteries

Tony,

Thanks for the updates.

When one is having serious concerns about low SG readings with Surrette FLAs, over an extended perios of time, RAISING the EQ voltage will be a good idea. The 62 V EQ voltage that you note is the absolute minimum that Surrette specs. I would strongly suggest that you raise EQ V to about 63 V or even a bit higher. When your battery SGs come into the target spec range, then lower the EQ voltage to 62 V again. EQ voltages should be temperature compensated. Just keep an eye on battery temperature and water levels.

You want to get these SG readings UP as quickly as you can, within reason. Raising the EQ voltage above the 62 V that you note will help you accomplish this, in my opinion.
Best of luck, Vic