Test results LiFePO4 glider batteries after 6 years

On 08/08/2018 11:30 PM, 2G wrote:
"the only instrument in your panel that
might draw a bit less current is a transponder"

I seriously doubt it. All modern avionics are designed to operate over a wide input voltage range; they have internal dc-dc conversion circuits that transform the supply voltage to a regulated, operating voltage. Trig, for instance, specifies an input voltage of 11 to 33 V.

Tom


So does an LX9000 count as a piece of modern avionics? 12 volts
nominal, 10-16 volts min to max. How about a Becker 4201 radio? 12.4
min, 15.1 max, 13.8 nominal. There's very little avionics used in
gliders that have dc-dc converters, they're included in transponders
because you can't generate 300 watt pulses using battery voltage, you
have to step it up with a converter.

Dave

The only one I could find specifically designed for aircraft is the MGL BAT-1 (anything else was only a voltmeter or ammeter):
http://www.mglavionics.com/BAT1.pdf
It does not have a coulometer, however. I have specified this for my new ASH31.

Tom

2G wrote on 8/9/2018 9:10 AM:
The only one I could find specifically designed for aircraft is the MGL BAT-1 (anything else was only a voltmeter or ammeter):
http://www.mglavionics.com/BAT1.pdf
It does not have a coulometer, however. I have specified this for my new ASH31.

Pilots that are don't require the alarm function can find small panel mounted
volt-amp meters like these from Amazon for about $15:

- WATERWICH DC12-24V/0.1-10A Dual LED Digital Multimeter Amp Voltage Meter
- TOOGOO(R)Dual LED Digital Voltmeter Ammeter DC 0-100V 10A Panel Amp Volt Meter

I'm not suggesting those two are the best choices, but I have used similar units
that worked well.

There are panel mounted units that include amp-hour/watt-hour readings, but are
larger. I use a charger for my instrument battery that shows amp-hour/watt-hour
readings during charge, so I can see the battery did accept the expected charge.
That's be satisfactory for years, so I haven't felt the need for amp-hour readings
in the glider; generally, my current drain in-flight varies only a little.

--
Eric Greenwell - Washington State, USA