Interesting behavior from PowerSonic battery

Steve Leonard wrote, On 5/23/2013 9:13 AM:
On Tuesday, May 21, 2013 4:32:29 PM UTC-5, 2G wrote: This is called
"cell reversal" and does occassionally happen. My question is why do
you think that you need a 14V battery? All modern aviation
electronics is designed to operate on a wide range of input voltage.
This is accomplished by a circuit called a "dc-dc converter" that
boosts the input voltage to a higher, regulated, internal voltage.
Tom

Well, 2G, where do you draw the line on "Modern" avionics? MicroAir
radio? Becker 3201 radio? Becker 4201 radio? Filser ATR500? I
have seen all of the above "crap out" on a 12 volt battery when my
Cambridge computer and nav keep on working.

Be happy with your 12 volt system, and don't be diss-ing on me for my
14 volt system, OK?

The Becker AR4201 is a "modern" radio, meeting the standard requirements
to transmit and receive at 10 volts. But, if a 12 volt battery has
dropped below 11 volts, it has so little energy left, it may not be able
to operate the 4201 in transmit mode; however, it should still receive
properly. If it won't receive with voltages between 10 and 11 volts, it
isn't operating properly, and I would send it in for repair.

The Cambridge computer and Nav can work on even lower voltages than the
10 volt specification for a transceiver, so they would work longer than
the radios.

The AR3201 is also a "modern" radio, and has the same voltage operating
specifications as the AR4201. Ditto for the ATR500. The Microair, at
least the earlier versions (don't know about the latest), is not a
"modern" radio, and has a much more limited voltage operating range than
the ATR500, AR3201, and AR4201.

Many thousands of pilots have (and still are) successfully operated
these very popular radios on 12 volts for over two decades. Since you've
had problems with all three radios that thousands of other pilots don't,
perhaps your installation was causing it; Possibly, your 12 volt battery
capacity was inadequate (battery too small or in poor condition), and
you simple ran out of charge. Adding a 14 volt battery to a marginal 12
volt system would increase the battery capacity, allowing you run longer.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)
- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm
http://tinyurl.com/yb3xywl