3 position switch, use 2 positions to save on inputs?

This Forum is designed to support and assist in the use of any/all FDS related Interface products.

Moderators: Curtis, Jetcos

Post Reply
kand
Posts: 213
Joined: Wed Feb 03, 2016 3:48 pm
Location: Buckinghamshire, UK

3 position switch, use 2 positions to save on inputs?

Post by kand »

Hi, jetmax user here with a sys1x board to drive my OH panel

I am sure I read that where you have eg a 3 position switch lets say for eng start, you only need to wire and assign 2 of the 3 switch positions because the software logic will identify that if positions 1&3 are not active, the switch must be in position 2?

Am I dreaming this or maybe confusing another product!

If its possible can somebody point me in the right direction, otherwise I will get all those additional switch positions wired up!

many thanks Keith

Jetcos
Posts: 1273
Joined: Fri Sep 30, 2005 2:42 pm
Location: Newmarket,Ontario
Contact:

Post by Jetcos »

Depending on the Avionics software you are using there are ways to tell the software that the switch is in the "OFF" position. 3 position switches for example need to know you went from ON to OFF in the aircraft, from OFF to ON or Start like the APU. (the ON position on the panel is actually an OFF position on the hardware)

Once you get the system it will all make sense.
Steve Cos
Vice President and Tech Support
Flightdeck Solutions (FDS)

MichaelYSSY
Posts: 738
Joined: Tue Jan 06, 2015 11:04 pm
Location: Sydney - Australia

Post by MichaelYSSY »

Hi Keith

I'm by no means an expert at SysBoard logic so I'll be looking to learn something here too.

In switching though there is an OFF position and that position doesn't require a wire and maybe that was the logic?

I'll be watching with interest.

Cheers
Michael

kand
Posts: 213
Joined: Wed Feb 03, 2016 3:48 pm
Location: Buckinghamshire, UK

Post by kand »

thx guys, using simA

not talking about momentary switches here, mainly rotaries

the sys controller knows if a switch is live/on, the sys controller "could" know how many swtich positions that switch has in real life (or should have or configurable). The logic would be that because APU start is not live, neither is APU off, then the switch must be set to APU on? this would save wiring an input for APU on

get my drift!

MichaelYSSY
Posts: 738
Joined: Tue Jan 06, 2015 11:04 pm
Location: Sydney - Australia

Post by MichaelYSSY »

Keith

The APU Start position may be "momentry" but you still need to tell the software that you want it to start the APU.

I think it's more about inputs than switches.

Michael

kand
Posts: 213
Joined: Wed Feb 03, 2016 3:48 pm
Location: Buckinghamshire, UK

Post by kand »

Yes, the start and off inputs would be connected so a start signal would be there, it's only the 3rd position which doesn't need to be sensed logically because by process of elimination if the other outputs are not set, the last position must be. I am using 3 position rotaries for most of my switches, this means the switch is always in a connected position (on-on-on) and the software is always

Anyway, it appears this is not a feature so I will need to wire the remaining 3rd outputs of my rotary switches

Cheers

MarkHastings
Posts: 956
Joined: Wed Jan 18, 2006 5:08 am
Location: UK
Contact:

Post by MarkHastings »

FYI. In the Sim-A Sysboard Controller to detect the Non-Wired position you use the Assignment 1 and Assignment 2.
Depending on which position isn't wired.....You assign the OFF Event of the switches each side of the non-wired input.

As an example :
For an APU switch : OFF ON START
Inputs : 1 2 3
If only inputs 1 and 3 are wired, you would assign the OFF event of inputs 1 and 3 to the APU ON function.
APU OFF = input 1
APU Start = input 3

If only inputs 2 and 3, you would assign the OFF event of input 2 to the APU OFF function.
APU ON = input 2
APU Start = input 3

It's not complicated once you get your head around Switch ON Events and Switch OFF Events. :)
Mark Hastings
Software Developer
Sim-Avionics

Mk882004
Posts: 6
Joined: Wed Jul 13, 2016 7:26 pm

Post by Mk882004 »

I've been watching this thread because I was wondering the same thing, I was thinking of saving inputs on the engine start switches, only wiring GND, CONT, and FLT, hoping then when no signal is received from the switch it would put it in the OFF position in the sim. What was the final ruling on this? Is that the way InterfaceIT works? Or do you have to have an input on all for options?

Jetcos
Posts: 1273
Joined: Fri Sep 30, 2005 2:42 pm
Location: Newmarket,Ontario
Contact:

Post by Jetcos »

Depends on what Avionics software you are using and which Interface program.

An OFF assignment can be assigned to the positions on each side of the Off position.
Steve Cos
Vice President and Tech Support
Flightdeck Solutions (FDS)

Post Reply