Is large charging current equal to equalization?

[paulcheung]

Hi,

Is high charge current to charge the flood acid battery equal to equalization? said if I charge the battery bank once every month with current equals to c6 to c7 rate for an hour or so in bulk charge mood with the inverter/charger. does it equals to equalization? do the same damage and soften the sulfating like the equalization?

The reason I ask is the inverter/charger (Magnum MS4448PAE) need a special control pad to start equalization which I don't have. The outback charge controller have the option to equalize but the PV current is not stable as the clouds always passing where I live. So I try to do it with the inverter/charge with the current from the grid.

Thanks.

[Mike90250]

No, high charge current does not "equalize" the battery. Equalize, is a special "overcharge" of half the cells, to get the "lesser" cells up to proper charge. Best done monitoring with a hydrometer.
Each battery mfg has a recommended profile for bulk, adsorb, float & equalize.

High current applied to batteries does not help them do anything except shed plate material and warp things from heat.

[paulcheung]

Ok thanks

[Sunking]

No EQ is a precise over voltage held on the batteries until the voltage and specific gravity equalize.

[paulcheung]

Dereck,

Aren't I missed you! This forum is not the same without you. Welcome back. Hope you doing well.

Thank you. Can you tell me what is the correct volts to set on the inverter for LBV cut out for 50% DOD?

[paulcheung]

The second bank of the battery I got seem have sulfating problem. it look like the dealer who has them did not keep them charge for a while, the batteries have more capacity and work lazier than the older ones, I am going to try to do an equalization on them. I have a few questions.

The batteries are Rolls S530 400amps @20 hours rating. 48 volts bank.

What is the voltage should I set for equalizing?
What amps should the controller set to limit?
How long should I equalize them for?
Should they be fully charged to floating before I do the equalization?
Any thing I need to be look out for?
Thank you.

[greenHouse]

Dittos on "Yo, Dereck!" Not that I've been around so much either ...

Equalization charges have their own unique charging profiles, when looking at current. But until you've seen a flattened Absorb current line, you aren't even ready to think about equalization. One interesting thing about both Absorb and Equalize charges is that =low= current can be an indication of sulfation, so best to get a baseline for future reference. Falling below the baseline during absorption is a strong indicator of sulfation, which must then be confirmed with a hydrometer and equalization charge. If there are any questions after that exercise, a complete cycle of the batteries to determine capacity is required.

[Sunking]

Dereck,

Aren't I missed you! This forum is not the same without you. Welcome back. Hope you doing well.

Doing better but still going through chemo treatment. Not fun. If I could get chemo treatments in Jamaica I would be there in a heartbeat. Here in Texas we have 3 inches of solid ice, and ganja is dirt cheap in Jamaica.

Can you tell me what is the correct volts to set on the inverter for LBV cut out for 50% DOD?

If I remember correctly you are running Rolls batteries?

I hate answering this because there is no real good answer. But I will give you two ways to do it.

1. Is the most accurate method. With your batteries under a normal load and discharging use a temperature corrected hydrometer, and when you see the SPG average among the cells reach 1.19 is 50% DOD. At that point measure the voltage and you got your number.

2. Less accurate but gets you in the ball park is 11.58 volts for a 12 volt system, 23.16 for 24 volt, and 46.32 for a 48 volt system.

[paulcheung]

Thank you.

Sometime good deal may turn sour from time to time, I got these second set batteries at $39000 JA each is about $367 US dollars each delivered; so I bite the bullet and bought them. But the are lazier than the older S460. I suspect the dealer leave these in their warehouse and haven't keep them charged. So I hope I can equalize them.

[Sunking]

Paul get a good hydrometer, and use it. It will tell you everything you need to know. Let me know if I can help.

[paulcheung]

I have one, I bought it from the battery shop, they use the same meter to test the batteries. I checked my battery bank a little while. the two banks are below 1175. I am using the grid to charge the S530 bank now and see how much it read when after 4 hours absorb.
Thank you.

[Sunking]

Paul 1.175 is 40 to 50% SOC or put another way 50 to 60% DOD. Your batteries are in trouble. 100 % SOC is up around 1.26 to 1.27

[paulcheung]

I know, I wonder if the meter tell the accurate reading. I put the batteries to charge by the grid whole night last night, after first 3 hours it take for ever to absorb charge. it only take 6~8 amps current. This morning I check the reading again, it said 1200, this morning is rainy day. I put the outback to Equalization for 3 hours. because the cloud I only get 5~10 amps. after the EQ, the reading of one cell on one battery say 1250 and the others are 1225.

I put this bank of the batteries in a discharge now and try to fully charge them with the grid again to see what happen.

Thank you.