This question concerns how to provide power to the D180 during different scenarios.
I have designed my electrical system to have two busses: 1) Main buss
and 2) Combination avionics/endurance buss. The avionics buss is powered through a switch and diode coming from the main buss or thru an endurance buss switch directly from the battery.
Now my dilemma: I would like the D180 to be alive during engine start (to monitor EMS parameters), so I need to power it without the avionics switch on. One option is to isolate the EFIS from the avionics buss with a rectifier diode array (it would then powered from the main buss OR avionics buss).
The D180 installation manual page 4-3 pin 15 shows an external backup power input. If I connected this to the main buss, would the D180 come on immediately, or does power need to be applied to the master power input first? Alternatively, should I perhaps power the main power from the master buss and the alternate power from the avionics/endurance buss?
In summary:
Option 1: Isolate the EFIS using diode rectifier array on main power input
Option 2: Power the EFIS from the main buss with alternate power from the endurance buss
If it makes any difference, I do have the backup battery option.
Don
I have designed my electrical system to have two busses: 1) Main buss
and 2) Combination avionics/endurance buss. The avionics buss is powered through a switch and diode coming from the main buss or thru an endurance buss switch directly from the battery.
Now my dilemma: I would like the D180 to be alive during engine start (to monitor EMS parameters), so I need to power it without the avionics switch on. One option is to isolate the EFIS from the avionics buss with a rectifier diode array (it would then powered from the main buss OR avionics buss).
The D180 installation manual page 4-3 pin 15 shows an external backup power input. If I connected this to the main buss, would the D180 come on immediately, or does power need to be applied to the master power input first? Alternatively, should I perhaps power the main power from the master buss and the alternate power from the avionics/endurance buss?
In summary:
Option 1: Isolate the EFIS using diode rectifier array on main power input
Option 2: Power the EFIS from the main buss with alternate power from the endurance buss
If it makes any difference, I do have the backup battery option.
Don