Float charging two 12V 34Ah AGM batteries

First posted
Friday August 16, 2013 13:42
Tuesday August 20, 2013 06:33

Battery charging lecture by Aaron at end of 310 Solar field trip on Thursday August 15, 2013 10:00-11:00 prompted us to check state of charge of our Two Harbor Freight 12V 343Ah AGM batteries. Battery neglect guilt too.

Battery 1 had been in the house with voltmeter measuring voltage from before June 4, 2013.

Battery 2 was in the garage in extreme New Mexico heat since the same time. 2 was last last solar charged with the HQRP charge/load controller.

Battery Basics: A Layman's Guide to Batteries.

Harbor Freight super-useful flashlights.

Batteries subjected to solar and grid recharging.

RAYOVAC rechargable work last long with Canon PowerShot SX160 IS camera if used promptly after charge. But do not last with Fuji A600.

Reason no 9V seen is that they are used in Harbor Freight digital multimeters. Dates recharged and sometime mA draw and voltage written on plastic tabs are attached to multimeters when battery inserted.

12V,34Ah battery 1 more than 24 hours after grid float charge.

Battery 2 more than 24 hours after grid float charge.

Float charger does not work in modified sine wave inverters. 

Monday August 19, 2013 21:51

Top Ten Myths of LEDs: #9 – “LEDs are expensive”

Truthdigger of the Week: Laura Poitras.


Voltage and current measured during float charge from grid.

Battery supplies power to float charger which powers red LED.

Float charger is not powered from the grid at this time.

Battery 2 in float charge mode from grid.

Video of battery 2 setup. Part 1. :(
Video of battery 2 setup. Part 2. :)

Harbor Freight float charge controller field trip after above working.
Sixty four float chargers plus more in the back of Albuquerque Harbor Freight.

Price $9.99. 

Photo taken with Tracfone LG 840G.

Clipped from ads.

How can any profit be made?

Battery life and charging is important for mobile devices.

Low power consumption for mobile devices, such as the Tracfone LG 840G, is important for length of operation and saving power.

LG840G admonishes to disconnect to save power when battery full.

Length of PC battery operation was another topic of conversation on 301 Solar visit.

Front of garage visited on battery 2 charging started to retrieve.

Linear 7805 voltage regulator regulates from a higher voltage, like 9 or 12V, to 5V.

Voltage drop from the higher voltage to 5V produces heat depending on the current drawn.

If the heat is too great, then a heat sink and heat conduction paste must be added.

Current in above Centronics printer to IBM PC parallel port cables not enough to require heat sink.

Heat sinks waste power. But this is way it was done in the past.

Intel X86 Haswell article link.



Mr Shahab Mozaffari got the facebook links started with one line facebook comment that the liked 'google aboulghassem zirakzadeh'..


Next Ms Katayoon Mazhari facebook notification that she wants to be friends.

Then in November 2012 Ms Sahar Mehrroz takes viz action.

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