[agirard7a]

Can someone let me know the best way to hook up a low presure oil light?
I plan to have my EFIS off on start up and want to make sure oil pressure on startup is sufficient. Thanks.

 

[Sam Buchanan]

Can someone let me know the best way to hook up a low presure oil light?
I plan to have my EFIS off on start up and want to make sure oil pressure on startup is sufficient. Thanks.

Put a tee in the fitting at the oil pressure sensor and install an automotive oil pressure switch. Be sure the switch turns "off" with pressure. I have this arrangement on my RV-6 and it works very nicely.

Also have an audio transducer in the circuit to remind me to turn off the master but you may not be as senile as I......

 

[Walt]

B and C Switch with print

 

[hecilopter]

Hobbs meter

The pressure switch I used for my Hobbs meter had an extra connector for a light. I hooked a big square amber light above my EFIS. It serves as a low oil pressure warning and a warning that your master is on when the plane is shut down.

 

[Wayne Gillispie]

If you have a GRT EIS, it can be wired to main bus and stay on during start up and display oil pressure or you can have small aux battery to power EFIS on startup. Since I already had a pressure transducer from GRT, I just used it.

Of course you can do as above post recommended and add another switch, wire, light and fuse.

 

[uk_figs]

Same as "Rooster"

Wired in master caution from the hobbs same as Rusty, also have the ground for the circuit switched by the Dynon such that any time the Dynon triggers a alarm the same light come on. Also acts as a "Master On" warning after shutdown. If you have ExpressPCB I can send you the schematic.

 

[Rupester]

As indicated above by a couple of posters, some Hobbs switches come with two contacts, one normally open that starts the hour meter with oil pressure; the other is normally closed and breaks a circuit on oil pressure. The latter is simply wired to the warning light on the panel. If the ignition is on with no oil pressure, the light is on. It goes out on start with oil pressure. (I recall the Hobbs devices are set at around 10psi O.P.)

 

[Sam Buchanan]

As indicated above by a couple of posters, some Hobbs switches come with two contacts, one normally open that starts the hour meter with oil pressure; the other is normally closed and breaks a circuit on oil pressure. The latter is simply wired to the warning light on the panel. If the ignition is on with no oil pressure, the light is on. It goes out on start with oil pressure. (I recall the Hobbs devices are set at around 10psi O.P.)

That's a great solution if you have a Hobbs meter. But a bunch of RVs don't have a traditional Hobbs switch because we use other methods of logging time. The tee and pressure switch works nicely for those situations so anyone who wants an oil pressure/master light can have one regardless of how hours are counted.