shop-talk
[Top] [All Lists]

Re: [Shop-talk] Float chargers

To: Jimmie Mayfield <mayfield+shoptalk@sackheads.org> definitions=2020-04-07_07:, , signatures=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-2004070129
Subject: Re: [Shop-talk] Float chargers
From: Pat Horne via Shop-talk <shop-talk@autox.team.net>
Date: Tue, 7 Apr 2020 10:23:22 -0500
Cc: Shop-talk@autox.team.net
Delivered-to: mharc@autox.team.net
Delivered-to: shop-talk@autox.team.net
References: <6e96465e-90bf-1fd6-b9f6-28be9abeedb4@sackheads.org>
Sounds like a question for interstate. 

Peace,
Pat

Pat Horne 
We support Habitat for Humanity


> On Apr 7, 2020, at 9:34 AM, Jimmie Mayfield via Shop-talk 
> <shop-talk@autox.team.net> wrote:
> 

The recent discussion about solar-powered float chargers has reminded me of 
an issue that I've yet to understand or resolve...

I have a Battery Minder 12248 (12V 2/4/8A) charger/de-sulfator with temperature 
compensation sensor.  While I've never been able to appreciably restore a dead 
UPS battery using the de-sulfation mode, it seems to work fine as a slow 
charger.  It has several modes -- gel-cell, AGM or flooded -- which, near as I 
can tell, adjusts the threshold voltage at which the charger switches from 
bulk-charge mode to float-charge/de-sulfation mode.

Every 12V battery that I've ever connected to the charger, even the old AGM 
batteries taken out of my UPS units, eventually reached the threshold voltage 
and switched over to float mode (usually within 30-45 minutes for a 
nearly-fully-charged battery).  Except one.

About 2 years ago I installed an Interstate battery from Costco (size 27F, 
890CA, 710CCA) in my truck.  It's a flooded battery and if I understand 
Interstate's spec correctly, its capacity works out to around 100Ah.  The 
battery has a resting voltage of 12.6V so it doesn't appear to have any shorted 
cells and has no trouble starting my truck.  So it seems to be a normally 
healthy battery, right?

Thing is...I've never seen my charger go into float mode when connected to this 
battery even when it was nearly new.  With the recent pandemic stay-at-home 
orders, yesterday I decided to connect my truck to the charger to stave off 
parasitic drain (measured to be 20-30mA) that may have accumulated over the 
past week of inactivity.  I'm currently at 16 hours (@4A) and it still seems to 
be in bulk-charging mode.  I have difficulty believing that the battery needed 
50+ Ah.

So what's going on here?  This is the only battery that I've come across that 
behaves like this.


_______________________________________________

Shop-talk@autox.team.net
Donate: http://www.team.net/donate.html
Suggested annual donation  $12.96
Archive: http://www.team.net/pipermail/shop-talk http://autox.team.net/archive

Unsubscribe/Manage: 
http://autox.team.net/mailman/options/shop-talk/patintexas@icloud.com

_______________________________________________

Shop-talk@autox.team.net
Donate: http://www.team.net/donate.html
Suggested annual donation  $12.96
Archive: http://www.team.net/pipermail/shop-talk http://autox.team.net/archive

Unsubscribe/Manage: 
http://autox.team.net/mailman/options/shop-talk/mharc@autox.team.net

<Prev in Thread] Current Thread [Next in Thread>