EMS multiple +5V outputs (Pin 18)

[Patrick J Wenzel]

G'day folks,

Our SV-EMS 220 harness is currently servicing two +5V outputs from pin 18, specifically the Dynon MAP sensor and a Ray Allen flap position sensor.

While reading the Aithre Shield EX 2.0 installation instructions I notice they suggest a +5V source or the pin 18 on the SV-EMS harness, which has a 300mA limitation.

I have no idea what the MAP and FPS are drawing so until that point I won't be adding the Aithre to the harness, but it begs the question...

What are people doing when they require multiple +5V feeds?

Cheers,

Pat.

 

[jakej]

G'day folks,

Our SV-EMS 220 harness is currently servicing two +5V outputs from pin 18, specifically the Dynon MAP sensor and a Ray Allen flap position sensor.

While reading the Aithre Shield EX 2.0 installation instructions I notice they suggest a +5V source or the pin 18 on the SV-EMS harness, which has a 300mA limitation.

I have no idea what the MAP and FPS are drawing so until that point I won't be adding the Aithre to the harness, but it begs the question...

What are people doing when they require multiple +5V feeds?

Cheers,

Pat.

Read page 158 of the install manual AD-V15.3. The limit is 300 mA however you also need 20 mA for the other sensors eg Fuel & Oil Pressure + MAP. IF that doesn’t work ( it should ) you can always use a 12vdc to 5vdc converter - they are very low cost/size/weight & available on line.

 

[ned]

I have three +5v sensors ganged under the cowl with no issues.

 

[jakej]

Ned, with respect - the 300mA draw for the Aithre is to be considered here the ‘standard’ Dynon sensors (3) draw a maximum of 20 mA total.

 

[Patrick J Wenzel]

Excellent Jake, thanks for the reference.

By the way I just finished reading an excellent book by a man with the same initials as yours. I noticed you made a couple of starring appearances throughout.

 

[Patrick J Wenzel]

For anyone who may happen to read this thread at a later date, the Aithre EX 2.0 draws approx 5 mA @ 5V.

In the case of our aircraft we are drawing less than 30mA of the 300mA limit, so no problem to splice yet another wire to poor old pin 18, clearly the workhorse of the harness.

 

[jakej]

Excellent Jake, thanks for the reference.

By the way I just finished reading an excellent book by a man with the same initials as yours. I noticed you made a couple of starring appearances throughout.

There's a lot of book reading going on at the moment .

Re Aithre - my bad (sorry to Ned as well) , I misread your post as indicating the Aithre draws 300mA whereas it's the Dynon that has the 300 limit on pin 18. In your case using pin 18 still give heaps of margin.

 

[vlittle]

I used a 25 pin d-sub (solder cup version) to distribute the 5V bias supply in my rocket. FMI http://www.vx-aviation.com/sprocket/photos/panel_elec/schematics-2/EMS.pdf

You also use a 15 or 9-pin d-sub or split one into a ground bus and a 5V bus.
Vern.

Jeesh it's been almost 14 years since I joined this forum. I gotta get a life!

 

[Patrick J Wenzel]

I used a 25 pin d-sub (solder cup version) to distribute the 5V bias supply in my rocket. FMI http://www.vx-aviation.com/sprocket/photos/panel_elec/schematics-2/EMS.pdf

You also use a 15 or 9-pin d-sub or split one into a ground bus and a 5V bus.
Vern.

Jeesh it's been almost 14 years since I joined this forum. I gotta get a life!

Genius! An ideal, tidy solution.

Thank you for sharing!

Pat.