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Master Switch Warning

Warning light from oil pressure switch

I have a warning light connected to a oil pressure switch for the hobbs. The pressure switch is wired with one + input and two outputs. One of the outputs is hot when there IS oil pressure which is connected to the hobbs. The other output is hot when there IS NOT oil prssure. The latter is connected to a oil pressure warning light. When you shut down and there is no oil pressure the light turns on and remains on until you shut off the master. I also have a GRT EIS that will turn it's warning light on when the engine shuts down and there is no oil pressure. I have the EIS switched so it is possible that I could shut off the EIS but not the master that is why I still need the seprate warning light.
 
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Leave your nav lights and strobes on all the time -- unlikely to miss that in a hangar. Saved my battery several times....
 
low oil press light

Ditto on low oil pressure warning light.

That bright red light is a great reminder after shutdown that the master is still on. Besides, it's nice to have a second warning source for an actual low oil press situation. :)
 
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Nav lights

My Nav lights are wired with out a switch. Master on. Nav lights on.:D And the they are LED, so minimal current draw. I make it a point to look back at the plane as I walk away just to double check.
 
tactile sensor mark 1 mod 2

I use the belt-and-suspenders technique for my round gauge panel.

Before I exit the aircraft, shutdown checklist includes "Master Off" (and "key on glareshield.")

If outside, I touch my master switch- far left end of the panel- to be sure it's down/off before fueling, tying down, or connecting the towbar for hangar entry or exit. (I also sight the key.)

Redundant by design, one catches omissions in the other. That's also why I put "flaps" in both post-start and pre-takeoff checks, after an unplanned "soft field takeoff" ;)
 
I have a warning light connected to a oil pressure switch for the hobbs. The pressure switch is wired with one + input and two outputs. One of the outputs is hot when there IS oil pressure which is connected to the hobbs. The other output is hot when there IS NOT oil prssure. The latter is connected to a oil pressure warning light. When you shut down and there is no oil pressure the light turns on and remains on until you shut off the master.

+1 on what Frank stated. Works great. Only managed to miss the light and leave the master on once :D Duh
 
We also have trim setting in two places on our checklists. It's very easy for a passenger to bump the trim if on the stick. Especially if you are holding the stick in your lap taxing as most of us do. We recheck it taking the runway along with canopy latched and mixture full rich.

George
 
I just have a habbit of looking at the switch and my EIS before closing the canopy. It hasn't failed me yet.
 
Right before I close the canopy I double check the 4 M's (also my shutdown checklist).

Music (radios)
Mixture
Master
Mags (EI)
 
I leave my beacon light switch "ON" so as I walk away, if the beacon light is on so is the master switch.

:cool:
 
switch

I have a warning light connected to a oil pressure switch for the hobbs. The pressure switch is wired with one + input and two outputs. One of the outputs is hot when there IS oil pressure which is connected to the hobbs. The other output is hot when there IS NOT oil prssure. The latter is connected to a oil pressure warning light. When you shut down and there is no oil pressure the light turns on and remains on until you shut off the master. I also have a GRT EIS that will turn it's warning light on when the engine shuts down and there is no oil pressure. I have the EIS switched so it is possible that I could shut off the EIS but not the master that is why I still need the seprate warning light.

Were did you get the switch with two outputs?
 
VAN's solution

The set-up I use with a pressure switch that powers Hour meter or warning light is actaully one suggested by VAN's.

"Hour meter (similar to Hobbs) activated by oil pressure switch, records engine time. System requires ordering both components (Meter and switch) separately. Optional oil pressure switch can be wired to run Hour Meter and illuminate a panel light if the oil pressure drops below 15 psi. Besides being a monitor should you loose oil pressure, this effectively works as a warning to turn the Master Switch off when the engine shuts down provided a large enough red light is mounted on the panel."

Oil pressure switch for activating Hour Meter and light
Part Number = IE SPDT PRES-15 SW
Price = $35.00
 
The set-up I use with a pressure switch that powers Hour meter or warning light is actaully one suggested by VAN's.

"Hour meter (similar to Hobbs) activated by oil pressure switch, records engine time. System requires ordering both components (Meter and switch) separately. Optional oil pressure switch can be wired to run Hour Meter and illuminate a panel light if the oil pressure drops below 15 psi. Besides being a monitor should you loose oil pressure, this effectively works as a warning to turn the Master Switch off when the engine shuts down provided a large enough red light is mounted on the panel."

Oil pressure switch for activating Hour Meter and light
Part Number = IE SPDT PRES-15 SW
Price = $35.00

Thanks Frank, I was looking everywhere except Van's catalog. I will order the switch today to replace existing Hobbs switch.
 
As we walk away from the jet, I sometimes say to the F/O.....


Dang, you left the beacon on.......


They always bite :D:D:D
 
Beacon

As an F/O I'm thinking that you (Capt) answered OFF when I read "Beacon" on the parking checklist!
 
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