JPI EDM 730 three position switch?

[jd21476]

I recently bought a used JPI EDM 730 with fuel flow. It came with all the probes and sensors and the fuel flow transducer.
In the manual it mentions a 3 position switch for fuel flow. It says EGT, ALL, FF. This did not come in the kit.

Do I need this switch and if so what function does it serve or not serve?

 

[Arrow76R]

The switch selects whether the digital scanning display along the bottom of the screen (NOT the "linear displays on the edge of the screen) shows EGT and Cyl temp or only fuel flow related items such as fuel used, etc. or all of the above. If there is no switch then (according to the schematic) you will see all of the parameters in the scanning digital readout. I wondered about the necessity of the switch when I had my EDM 830 installed but now I find that in cruise flight I leave the switch to display just fuel related items. During climb and descent I switch to EGT to watch for "shock cooling" and cyl temps during climb..

 

[Bill]

It’s in the JPI POH.

 

[asicer]

It’s in the JPI POH.

I also noticed it's in your plane (third pic and last pic)
https://www.pilotsofamerica.com/com...lunch-this-saturday-6-13.126513/#post-2931778

BTW, what is "H/H COMM"?

 

[Bill]

I also noticed it's in your plane (third pic and last pic)
https://www.pilotsofamerica.com/com...lunch-this-saturday-6-13.126513/#post-2931778

BTW, what is "H/H COMM"?

Jack that connects a hand held comm to the third external comm antenna.

 

[jd21476]

So I did read it in the JPI POH but I guess my question is, do I need it? It looks like I can cycle through the menus just fine without it. So Im not sure of its overall purpose unless it is like a quick select switch

 

[WannFly]

I have that switch with 830. Have kept it at All, since I got it. Skip it

 

[jd21476]

So if I dont install the switch then it defaults to ‘ALL’?

 

[Bill]

So if I dont install the switch then it defaults to ‘ALL’?

Good question, but I don’t know the answer. You may have to tie a couple of the leads together to get the ALL the function, I’d call JPI and find out for sure.

 

[jd21476]

I called JPI this morning and they said I do need the switch for it to work properly so they are sending me one for free. That was nice.

 

[Martin Pauly]

So I did read it in the JPI POH but I guess my question is, do I need it? It looks like I can cycle through the menus just fine without it. So Im not sure of its overall purpose unless it is like a quick select switch

This is for convenience and to save time. There are A LOT of parameters to cycle through; this switch makes it a little easier/faster to look at just temperatures, or just the other stuff - or to cycle through all of them.

- Martin

 

[jd21476]

So its not technically needed? Because the tech support at JPI said it was needed to “work properly.” Maybe I took that to mean just to work in general

 

[Martin Pauly]

So its not technically needed? Because the tech support at JPI said it was needed to “work properly.” Maybe I took that to mean just to work in general

If JPI says it's needed, I assume they are referring to an approved compliant installation. While that's important, from a purely technical perspective, whatever connection that switch makes when set to cycling through ALL parameters could be hard-wired, and you wouldn't need that switch on the panel.

- Martin

 

[jd21476]

Well, they are sending it for free and I always like originality with things so of thats how it is supposed to be then I would like it connected.

 

[Martin Pauly]

Well, they are sending it for free and I always like originality with things so of thats how it is supposed to be then I would like it connected.

I would do the same thing. The switch is useful, it's a time saver.

- Martin

 

[jd21476]

Aaauuuuggghhhh!!! JPI!!!! So originally for the EDM 730 install we were missing some thimbles. My mechanic called JPI and ordered the thimbles, they sent the clamps. Wrong part! So then after calling them again they sent the right part. Then I called for a 3 way switch. They said they would drop it in the mail last Monday. By Friday it had not arriver. Im only 80 miles away from their shop. I called them on Friday and said I would pay for overnight shipping with Saturday delivery because I really needed the switch. Saturday came and went and after they charged $35 for shipping it still did not arrive.
At this point Im at my wits end. The plane has now been in the shop for two weeks for an install that should have taken a day or two and I still dont have the switch.

Aaaaauuuuuggghhhhh!!!