lndwarrior
Well Known Member
I have been seeing a repeated problem with my electrical system that I am trying to figure out. Some things to know:
- I built the plane and designed the wiring system based on the Z-11 diagram.
- It has worked well for 300 hours
- engine is an O-235
- 40 amp B&C alternator with 300 hours on it
- B&C LR-3 voltage regulator with about 30 hours on it
- EarthEx ETX680 battery 300 hours as well
- Electronics International Volts/Amps meter set up in a LOAD Meter arrangement with matched EI shunt
- very low amp draw electrical system - about 10 amps with everything turned on (VFR panel, led lights, etc)
I have noticed my battery voltage dropping when it has not been flown in a while.
EarthEx says either I have a parasitic drain going on when the master is off or I have a bad battery.
So far I have not had the time to trouble shoot what might be draining the battery. I do have an Always On bus for LED cabin light, USB port and possibly other item that I cant remember right now.
My normal/average total amp draw in flight is around 7 amps.
Yesterday I checked the battery with a portable amp gauge and it was reading 12.9 amps - below the 13.3 that is typical for this battery.
The engine started just fine and I did a short MX flight directly over the airport. For the 10 minutes I was in the air the amp meter was reading about 25 amps, though this was varying up and down by an amp or two.
I have never seen this high amperage (alternator output) before. I have high and low voltage warning lights and a stuck starter light. None of the warning lights lit up during the flight.
So, is the 25 amps I saw simply just normal? Is this a case of the alternator charging a low battery? Again, the max load from my electrical system is around 10 amps, and everything was not turned on during the flight.
I know I need to check the system for parasitic drain but right now I'm just trying to understand that my charging system is doing.
TIA
Gary
- I built the plane and designed the wiring system based on the Z-11 diagram.
- It has worked well for 300 hours
- engine is an O-235
- 40 amp B&C alternator with 300 hours on it
- B&C LR-3 voltage regulator with about 30 hours on it
- EarthEx ETX680 battery 300 hours as well
- Electronics International Volts/Amps meter set up in a LOAD Meter arrangement with matched EI shunt
- very low amp draw electrical system - about 10 amps with everything turned on (VFR panel, led lights, etc)
I have noticed my battery voltage dropping when it has not been flown in a while.
EarthEx says either I have a parasitic drain going on when the master is off or I have a bad battery.
So far I have not had the time to trouble shoot what might be draining the battery. I do have an Always On bus for LED cabin light, USB port and possibly other item that I cant remember right now.
My normal/average total amp draw in flight is around 7 amps.
Yesterday I checked the battery with a portable amp gauge and it was reading 12.9 amps - below the 13.3 that is typical for this battery.
The engine started just fine and I did a short MX flight directly over the airport. For the 10 minutes I was in the air the amp meter was reading about 25 amps, though this was varying up and down by an amp or two.
I have never seen this high amperage (alternator output) before. I have high and low voltage warning lights and a stuck starter light. None of the warning lights lit up during the flight.
So, is the 25 amps I saw simply just normal? Is this a case of the alternator charging a low battery? Again, the max load from my electrical system is around 10 amps, and everything was not turned on during the flight.
I know I need to check the system for parasitic drain but right now I'm just trying to understand that my charging system is doing.
TIA
Gary