R

rightrudder

Well Known Member
Maybe this would be better over in "Glass Panel," but I thought there might be some general interest. Do most EFIS setups include a Hobbs function? And how many of you run a separate Hobbs meter? I've got the GRT Sport SX (still in box) and I can't find any mention of Hobbs in the user manual.
 
Dont know about the Sport, but with the setup in my plane-----first generation screens, the EFIS has a log book function, and the EIS has a Hobbs.

The EFIS does display the Hobbs as sent from the EIS---------at least as far as I understand how the system works.

You do need to tell the EIS when to start the time running as I recall, choices were based on either RPM, or oil pressure.
 
I have the GRT Sport as well, there is a automatic flight log feature tied to airspeed if you have the built in GPS. This logs flights with day/timestamp and inserts waypoints and pre-populates a flight log you can edit further but I'm pretty sure there is no hobbs meter built into the GRT sport.

I also have a AFS 2500 engine monitor unit and it does have a built in hobbs/tach meter that I use.
 
Mike S said:
Dont know about the Sport, but with the setup in my plane-----first generation screens, the EFIS has a log book function, and the EIS has a Hobbs.

The EFIS does display the Hobbs as sent from the EIS---------at least as far as I understand how the system works.

You do need to tell the EIS when to start the time running as I recall, choices were based on either RPM, or oil pressure.
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Thanks, Mike and Russ.

I should be good then, since the EIS is part of the Sport SX system. I was a little surprised to see the separate EIS display in the box, as the primary display and EIS work together. Luckily, my panel plans are pretty simple, so there's plenty of real estate for another rectangular cutout.
 
David Paule said:
You can remote-mount the EIS.

Dave
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Yeah, I thought about that. Certainly a possibility; I just don't know how useful the extra screen would be, or whether I'll need access to the EIS's buttons down the road. For a cleaner panel, one thought was to mount it inside the map box, high up so there's still some storage underneath.
 
The GRT EIS has the Hobbs timer in it.
GRT recommends starting with the Sport off, unless you have a secondary buss to run it. But the EIS can be on at start up, and can be set to alarm if there's no oil pressure. That does require mounting it on the panel.
 
BobTurner said:
The GRT EIS has the Hobbs timer in it.
GRT recommends starting with the Sport off, unless you have a secondary buss to run it. But the EIS can be on at start up, and can be set to alarm if there's no oil pressure. That does require mounting it on the panel.
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So I'll just wire the PFD and EIS to power up with the avionics master switch, and set the oil pressure to trigger the Hobbs at 5 psi or something. I'll get an annunciation through the PFD if pressure drops too low, and I believe that triggers the warning lamp as well.

I think my main screen will have all the engine monitoring in a strip along the bottom.
 
rightrudder said:
Yeah, I thought about that. Certainly a possibility; I just don't know how useful the extra screen would be, or whether I'll need access to the EIS's buttons down the road. For a cleaner panel, one thought was to mount it inside the map box, high up so there's still some storage underneath.
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You can remote mount and have the three buttons mounted at a different location but I use the EIS screen at least for my initial start up to very oil pressure and a few other specific alerts beside the EIFS. Also, time to time you will need to have access to the screen to setup or change the AUX or other settings so if you do have space in your panel, I highly recommend having it accessible.
 
rightrudder said:
So I'll just wire the PFD and EIS to power up with the avionics master switch, and set the oil pressure to trigger the Hobbs at 5 psi or something. I'll get an annunciation through the PFD if pressure drops too low, and I believe that triggers the warning lamp as well.
I think my main screen will have all the engine monitoring in a strip along the bottom.
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They are not avionics. They are flight instruments.

The EFIS has dual power inputs. Connect one power lead to the main bus, and the other to the EFIS backup battery via a switch. Flip on both switches when you sit down. The EFIS boots while you buckle in, and the backup battery does not allow it to brown out during start.

Connect the EIS to the main bus so it comes on with the master. Mount it where you can always see it, and use it as a fuel totalizer. Display fuel tank levels on the EFIS. That way you're always running two separate fuel status indications, one based on fuel flow and the other based on fuel level.

The EFIS will display whatever fuel warnings you choose. Mine is set to warn at 10 gallons on the totalizer, or either tank at 3 gallons indicated. The EIS Big Red Light is triggered by only one parameter, that being oil pressure.

Hobbs ON is whatever RPM threshold you choose.

You don't have to use the ugly EIS faceplate. Just back mount the case, with individual holes for the buttons.

ngbpmu.jpg
 
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Another perspective:

My EIS is mounted sideways on the fwd "switch panel" on the right side of the -8. It can be seen in a pinch, but I find the display useless with the dual GRT Horizon screens dominating the panel. In the several years I've been flying this thing, I've never touched the EIS - it could be mounted in the tail, for all I care.

Hobbs info is available on both of the big screens, so no issue there (and certainly no need for an extra mechanical hobbs IMHO).

Brown outs are no problem on engine start because the screens are off until the engine is running. Oil pressure is the only thing I'm even slightly worried about and a simple red LED wired to an oil pressure switch tells me all I need to know. Lycoming gives you a long time for oil pressure to register, and the screens are usually up and running by then anyway.
 
Thanks, Michael. I value all input here.

In the interest of simplicity, I want to avoid a backup battery. I'd probably think differently if my ship's mission was anything other than day VFR, but if the panel goes (or the entire electrical system for that matter), I'll still have my battery-powered GPS, a sectional, a list of key frequencies on my kneeboard and a handheld radio. My Lycoming is box-stock with magnetos, so the pistons ought to keep churning.

My build is not fancy, but I prefer it that way!!
 
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About the same as my ancient 2006 vintage WS. One of which is currently on its way back to GRT because it won't paint anything on the display.
 
Mike S said:
At least you are smart enough to have already saved your configuration settings.
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Ahh, yes, grasshoppah, never leave home without software to reload and the config backup after you have done so :).
 
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