Greater Southwest Aero Modelers Chat Forum

R/C Electronics => Batteries And Chargers => Topic started by: Bill Bradford on April 10, 2019, 10:45:17 AM

Title: Under Load Battery Voltage Testing
Post by: Bill Bradford on April 10, 2019, 10:45:17 AM
I have a Futaba BR-3000 meter for testing my receiver batteries. However, I recently discovered that it does not test the battery with a load on it after I compared it to a receiver switch that had voltage level lights. While the Futaba tester showed 99% capacity remaining, the receiver switch showed red, a level indicating a very low voltage. This was proved correct when I tried to move the servos and they were very sluggish. I charged the battery and the switch showed green and I had normal servo function. I researched the Futaba meter and found out that it does indeed test without a load.

I plan to put a resistor in series with the tester leads in order to test the 6 volt battery under load. In order to produce an approximately 1 to 2 amp load, I will use a 5 ohm resistor. Does this make sense to you guys?

Thanks,
Bill
Title: Re: Under Load Battery Voltage Testing
Post by: Mark Fuess on April 11, 2019, 04:58:36 PM
Yes.
Title: Re: Under Load Battery Voltage Testing
Post by: Bill Bradford on April 12, 2019, 11:25:35 AM
Thanks, Mark.
Title: Re: Under Load Battery Voltage Testing
Post by: Steve Rogers on April 13, 2019, 07:03:27 AM
Make sure you have a 5 or 10 Watt resistor. It will get hot.
Title: Re: Under Load Battery Voltage Testing
Post by: Bill Bradford on April 14, 2019, 12:33:03 PM
Thanks, Steve. I plan to use a 10 watt resistor.

Bill