Do I need a Hobbs and an EFIS?
 

My efis vendor provides a hour and tach meter. Does this mean I can omit the seperate Hobbs/tach? If so is that advisable? Saving some money and panel space would be great.

Schu

I certainly would & did with the -12.

Don't need it
 

I have the AFS 2500 engine monitor. It has flight and tach times. That's all you need.

My GRT EIS/EFIS provides all the Tach and time recording functions I need - and I haven't had a Hobbs in any airplane I've owned for 25 years!

If this is going to be an IFR plane, I believe you will need a clock/watch that you can reset it. I know it has a certain requirement but I don't remember the details. I use the one that is built in my transponder.

Mehrdad
RV7A - IO360M1B

Both of my Dynon's have hobbs features and count up and count down clocks.

No need for either a hobbs or a clock.

They do but I found them not very usable for IFR...probably because I only have a sigle Dynon.

The easiest way to get the required IFR timer is to buy an oven timer from Radio shack..They work really well for timing approaches.

Frank

One nice thing about the hobbs meter is it probably won't get upgraded. When you decided to switch from steam to glass or upgrade your glass you will still have the hobbs meter showing the total hobbs time.

I suspect you can manipulate the hobbs time on glass systems but I haven't tried.

That's about the only "pro" hobbs meter thing I can think of. That and you can stick your head in the plane anytime and see the total time without turning anything on.

Somebody with a 12 was grounded recently with a bad oil pressure sender. Anybody know if the oil pressure switch for the hobbs could be used as an independent low oil pressure warning? I guess it depends on how much pressure is required to close the switch.

Yep, they can be set to any number you like.

By ?12?, I?m assuming you are talking RV-12. If that is the case, there is no need for such a warning with the Dynon. You simply set the alarm to go off at a given high or low oil pressure. You then get a red bar across the bottom of your screen and a tone in your ear. As I said, no need for a separate alarm.