Maganum 4024 / battery smell

[Brett G]

Hi all, I've been working on a major electrical upgrade for the last month and a half and today was the day to test everything.  It's a 24 volt system.  The batteries are brand new and they were manufactured in April of this year.  All of the tests went fine until I applied the AC power to the inverter and it's at that point that the batteries started smelling like sulfur so I turned off the breakers.  My multimeter has a battery test mode so I tested all batteries (6 volt) and they check out just fine.  Testing all batteries together gives me 25.5 volts.  With the AC on and applied to the inverter, the batteries were being charged at 29.8 volts.  Is 29.8 way too hight?  I'd appreciate any suggestions.  Thanks in advance

[ol713]

  HI;
     I think the answer is  YES.   Went thru that about a year ago with
     my solar controller.   Was going thru batteries about every 4 yrs
     or so. Found too many volts being charged.
     Also compare with coach batteries with engine running.
                                     Good luck,    Merle.

[luvrbus]

Most are 29.6V for lead acid flooded batteries for the bulk charge, the float charge should be around 26.4V you don't have the float charge set to high do you ?

[Lostranger]

Do you have the remote (wired) control panel for your inverter? If not, you need to get one. Gives you much greater control of all inverter functions, and its display gives constant system voltage. Do you have the inverter set to charge the type of batteries you're using. Since you're getting serious off gassing, I'm guessing that your batteries are flooded lead acid. The inverter may be set to charge some other type.

Is the inverter new? If so, contact your dealer. The folks we dealt with were happy to help with our early questions.

I use four 8D AGMs wired series/parallel for 24 volts. On occasion, my voltage reads 29 for a while on the control panel. I suspect that the inverter is doing an equalize charge at that point. That may be what's happening with yours.

Let us know what you learn.

Jim

[muldoonman]

What Jim said. Get the Magnum ME Battery Monitor Kit. Think it's a direct plug in with a 2 amp fuse protection. You can set it for the different batteries and it does make a difference. Think they are $180 bucks. Well worth it.

[gumpy]

You're setting is too high, unless you have a battery temperature sensor attached.

Set the bulk at 28.8. Float at 27.2. 

29.8 will boil your batteries, as you have already smelled.

[Brett G]

I do have the battery temp sensor, battery monitor, as well as the remote but haven't hooked up the remote yet.  Everything is new.  Within about 10 seconds of turning on the AC to the inverter, I can smell it.  That's really quick, don't you think?  Without the remote, default settings should be set to this..

Flooded-Liquid Lead Acid
12V = Absorb 14.6 VDC, Float 13.4 VDC:
24V = Absorb 29.2 VDC, Float 26.8 VDC

[eagle19952]

What type batteries are they ?

IIRC, AGM batteries do not need nor should they be equalized...

Here is an excerpt from the internet...

"Equalizing AGM and other sealed batteries

"Equalizing AGM and other sealed batteries is a bit more tricky. The bubbling electrolyte results in some loss; electrolyte vapor exits the vent caps. However because there is no way to replace the lost electrolyte it is obvious that a different strategy is required. I couldn't find any manufacturer that recommended equalizing Gel batteries.These batteries are highly sensitive to over-charge and equalizing is not going to work for them. However although I did find a manufacturer that definitely did not recommend equalizing their AGM batteries (Trojan) I did find at least one manufacturer (Lifeline) that did recommend equalizing their AGM batteries.

Lifeline use the term "Conditioning". They say this should only be done when the battery is showing loss of performance due to having spent extended time in a partial or low state of charge, or that don't often get charged above 90%  (Cruisers that never come to the dock please take note!)

Lifeline AGM instructions:
To apply a conditioning charge, first go through the normal charge cycle to bring the battery to full charge. The conditioning charge should then be applied by charging for 8 hours. At 77°F (25°C), the conditioning voltage should be set at 2.58 VPC (15.5 volts for a 12 volt battery). The conditioning voltage at other temperatures is shown in Table 5-2. By using the temperature compensated conditioning voltage, batteries that are not in controlled temperature environments may be conditioned without bringing them to room temperature. If temperature compensation is not available, it is best to bring the battery as close to room temperature as possible before applying the conditioning charge".

I would suggest that without the remote installed the charge inverter is defaulting to wet cell mode... not good by most accounts.

IF yours are wet cell, then they should taper off to lower eq charge voltage rapidly, if all is well within.

[Brett G]

These are the batteries I purchased.  Energizer Golf Cart Battery - Group Size GC2 http://www.samsclub.com/sams/energizer-golf-cart-battery-group-size-gc2/prod6750008.ip?navAction=push

[eagle19952]

These are the batteries I purchased.  Energizer Golf Cart Battery - Group Size GC2 http://www.samsclub.com/sams/energizer-golf-cart-battery-group-size-gc2/prod6750008.ip?navAction=push

so, the next question would be, how many minutes did you apply the charge ? if longer than a few did the charge v taper off ?

did you check each individual cell... is one cell/battery defective ? specific gravity, by optical hydrometer or bulb type ?

Example readings:
Three 6 volt batteries

   Cell #1   Cell #2   Cell #3   Condition
Battery A   1.250   1.225   1.250   Recoverable
Battery B   1.275   1.250   1.225   Recoverable
Battery C   1.200   1.250   1.275   Open Cell
Battery C has an Open Cell
because the difference between Cell #1 and Cell #3 is .075, more
than .05.

Any battery that has a Short or Open Cell needs to be replaced.  you only need to replace the bad battery with another used or new battery.

[gumpy]

Have you been running 12v off your battery bank prior to charging?

You're 12v is not connected properly. They way you have it, you'll draw down 2 of your 8 batteries. This will affect the overall voltage of the whole bank, making the inverter
think it is lower than the other 6 really are, so it will try to compensate, which could cause overcharging of the other 6 (and ultimately undercharging of the 2 12v feeds.

That vanner doesn't seem to be doing anything the way you show it.

You need another wire between the two 12v half positives. 

[Iceni John]

What Jim said. Get the Magnum ME Battery Monitor Kit. Think it's a direct plug in with a 2 amp fuse protection. You can set it for the different batteries and it does make a difference. Think they are $180 bucks. Well worth it.

Wholesale Solar generally has the best Magnum prices  -  the remote is only $149.00 there:  http://www.wholesalesolar.com/products.folder/inverter-folder/ME-RC50.html
Magnum also makes a more expensive remote with extra functions.

John

[Nick Badame Refrig/ACC]

Hi Brett,

About 8 years ago when I used to use led acid batteries, out of my bank of 8 batteries, one was totally

dry without acid the day I purchased them. It resulted in a bad egg smell at the first charge and blew the

top off of the dry battery.  This could be something to check.. Open them all up and do a hydrometer test!

Good Luck
Nick-

[Brett G]

Gumpy, I think you got it!  I'll report back.  Thanks all

[Brett G]

Me again.  What Gumpy said looks to be the issue.  I do have that wire connected in one of my other drawings.  Guess I didn't want to follow that one.  I'll still report back.  https://docs.google.com/drawings/d/1Us02X_ZduDrJoGBe2yOWzcjrVVp0puUTW0Kp-LTj9J8/edit?usp=sharing