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General Category => General Discussion => Topic started by: labusker on December 10, 2020, 02:19:58 PM

Title: External Fan on Aux1
Post by: labusker on December 10, 2020, 02:19:58 PM
I would expect to want my fan to come on during high charging which would relate to high charging current. Why is there not a software setting to control this with a current value instead of a voltage value on my Classic 150?
Title: Re: External Fan on Aux1
Post by: boB on February 06, 2021, 12:57:59 AM

Probably isn't there because there has been no call for that Aux function before ?

Is it a vent fan for flooded lead acid batteries you want to control ?  That is normally controlled by voltage of the battery, which would more than likely happen after charging at high current for a while.   

Might be nice to have an aux function that turns on when a prescribed amount of power or current is happening though.

Title: Re: External Fan on Aux1
Post by: Vic on February 06, 2021, 12:17:35 PM
Hi labusker,

As boB noted,   the general need for a vent fan when using FLA batteries,   is when the battery voltage approaches and exceeds the battery Gassing Voltage.

During most of the Bulk charge stage,  the battery is not Gassing,   and until this voltage is not reached,
and exceeded,   there is essentially no Gassing,   irrespective of the Charge Rate (current).

SO,   IMO,   the existing Aux Vent Fan selections should meet your fan control needs in dispersing Hydrogen gas,  with an appropriate fan and configuration.

Vic
Title: Re: External Fan on Aux1
Post by: labusker on February 26, 2021, 09:06:05 AM
The manufacturer states that the higher the charge voltage, the higher the rate of evolution. I presume evolution means gassing. They do not state the actual gassing voltage. So what voltage can be recommended to turn on a vent fan? My 6v batteries float at 6.9v and absorb at 7.35v. Thanks.

Equalize question: If I only discharge my batteries 20-30% every night will an equalization charge ever be needed?
Title: Re: External Fan on Aux1
Post by: ClassicCrazy on February 26, 2021, 12:12:37 PM
Quote from: labusker on February 26, 2021, 09:06:05 AM
The manufacturer states that the higher the charge voltage, the higher the rate of evolution. I presume evolution means gassing. They do not state the actual gassing voltage. So what voltage can be recommended to turn on a vent fan? My 6v batteries float at 6.9v and absorb at 7.35v. Thanks.

Equalize question: If I only discharge my batteries 20-30% every night will an equalization charge ever be needed?

I think your answer on gassing voltages for batteries was answered by Vic above. He said that not so much in Bulk but much more so in Absorb.

Equalizing is for flooded lead acid batteries to help bring the specific gravity up on any cells that may be lower than the others. You determine this by taking samples of the electrolyte . Though it doesn't hurt to do regular equalize cycle  - but taking the samples can tell if the equalize cycle was long enough to help cure any cells that were low.
The reason particular cells might go low is based on lots of factors but some like imbalanced wiring of parallel strings of batteries can be a larger factor.

Larry
Title: Re: External Fan on Aux1
Post by: labusker on February 28, 2021, 08:19:47 AM
IS IT TRUE THAT BATTERIES IN SERIES CANNOT EQUALIZE. aLL MY 8 BATTERIES ARE IN SERIES.
Title: Re: External Fan on Aux1
Post by: ralph day on February 28, 2021, 10:55:47 AM
Not true.  My batteries have always been in series and they eq just fine.
Title: Re: External Fan on Aux1
Post by: ClassicCrazy on February 28, 2021, 01:32:30 PM
Quote from: labusker on February 28, 2021, 08:19:47 AM
IS IT TRUE THAT BATTERIES IN SERIES CANNOT EQUALIZE. aLL MY 8 BATTERIES ARE IN SERIES.

All the cells in a battery are in series so not much different if all the batteries are in series too.

Larry
Title: Re: External Fan on Aux1
Post by: Vic on February 28, 2021, 10:06:50 PM
Hi labusker,

YES,   evolution is the evolving of gas  --  Hydrogen and Oxygen.

For a 48 V Flooded battery bank (NOT Lead Calcium),   Gassing voltage would probably begin around 56 V.   So setting the fan operation voltage at this,  or,  slightly lower should serve well,  IMO.

Vic
Title: Re: External Fan on Aux1
Post by: labusker on March 01, 2021, 07:50:53 AM
THANKS FOR ALL YOUR REPLIES.