Alarm wiring from HS-34 to audio panel

[bmarvel]

Dynon Support:

BACKGROUND: I have a D-100, HS-34, AP-74 with two servos and EMS D-10 all connected on DSAB.  We have elected to use the HS-34 for EFIS/EMS alarm outputs.  Per the install manual I've taken this output from pin 25 of the HS-34 and routed it to the volume pot, and then taken that output to the audio panel.  That's the source of my question.

QUESTION: The audio panel (PS Engineering 6000B) shows pins for hi and lo connections for everything, including unswitched inputs like the audio alerts from the HS-34.  There is a pin in the audio panel for the audio alert input from the volume pot and there is a pin for the corresponding lo connection.  However, there is no corresponding lo wire defined in the Dynon install guide for this pin in the audio panel.   For the alarm to work properly, do I need to connect the audio panel lo pin at all since all avionics share a common ground, or do I need to take a wire from the HS34 ground pin (17) and connect this to the designated lo pin on the audio panel?    

Thanks
Bill Marvel
RV-8A flying with Dynon
Zenith 801 being built with Dynon

 

[dynonsupport]

It looks like it's a differential input, which would imply that the lo pin would need to be grounded (either through a Dynon ground pin or any other common ground). You'll want to check with them thought to make sure of that though.

 

[jakej]

Bill

"Lo" connection is not needed in this situation.

Jake J

 

[bmarvel]

Thanks, Jake. That is the way I had it set but wanted to know for certain before I closed things up any further.

Bill