tonyjohnson
Well Known Member
I am trying to decide which switch to use for the Master/Alt function.
The AeroElectric Connection by Bob Nuckolls contains two different schemes. When discussing the function of switches he recommends a 2-3 switch. The 2-3 would turn on both the battery master and the alternator field at the same time.
The Z-11 diagram for the generic airplane shows a 2-10 switch for this function. The 2-10 would be progressive, in that it the first position up would turn on one of the functions and the next position up would add the second. The diagram seems to show that the first position up should turn on the battery and the second position up adds the alternator field. This would seem to turn off the alternator before the battery, and leaves open the possibility that leaving the switch in the first position up would have the battery on and the alternator field off. I have read that one should never turn off the alternator when the engine is running. Therefore I am a bit confused about the 2-10 switch recommendation.
If I use the 2-3 plan, it is pretty simple and would eliminate the possibility of having the battery master on while the alternator is off. If I wanted to shut down the alternator for some reason, I could pull the alt breaker.
Any electrical gurus out there who can help me understand this?
Thanks,
Tony
The AeroElectric Connection by Bob Nuckolls contains two different schemes. When discussing the function of switches he recommends a 2-3 switch. The 2-3 would turn on both the battery master and the alternator field at the same time.
The Z-11 diagram for the generic airplane shows a 2-10 switch for this function. The 2-10 would be progressive, in that it the first position up would turn on one of the functions and the next position up would add the second. The diagram seems to show that the first position up should turn on the battery and the second position up adds the alternator field. This would seem to turn off the alternator before the battery, and leaves open the possibility that leaving the switch in the first position up would have the battery on and the alternator field off. I have read that one should never turn off the alternator when the engine is running. Therefore I am a bit confused about the 2-10 switch recommendation.
If I use the 2-3 plan, it is pretty simple and would eliminate the possibility of having the battery master on while the alternator is off. If I wanted to shut down the alternator for some reason, I could pull the alt breaker.
Any electrical gurus out there who can help me understand this?
Thanks,
Tony
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