Plasma III Tachometer

[dodsond]

The Lightspeed Engineering Plasma III installation instructions show shielded wire for the tachometer output and specifes the sheild be grounded.  The harness that comes with the D-120 has 22 ga unshielded wire and no dedicated signal ground for the tachometers.

My airplane is fiberglass, so no airframe ground is available.

Who can recommend a connection scheme?  I could just use the Dynon plain wires and leave the Plasma III sheilds unterminated.  But it seems best to replace the Dynon wires by re-pinning the Dynon D-Sub with with the shielded wire which would also mean re-pinning one of the goound connections with the shields.  The sheilds could be grounded to the D-120 case I suppose, or even to the ground bus directly.

Any other connection schemes?

Doug Dodson
Glasair II-S FT

 

[jakej]

"Dynon D-Sub with with the shielded wire which would also mean re-pinning one of the goound connections with the shields."

Doug

That's the way I'd do it, neater and 'safer'.

Jake J

Oz Glasair IIS FT

 

[dynonsupport]

Personally, I wouldn't worry about the shield. The current used in this circuit is minimal and we've never heard of interference.

 

[PhantomPholly]

You may also wish to pull the serial number off of your control box and confirm with Klaus that it actually outputs 10v. Some of the earlier boxes output 5v, which is not enough to tickle the Dynon.