Triggering / powering aircraft components only in "energized state"

[OmniAtlas]

Hello, would appreciate any advice from the community or knowledgeable cockpit builder on how to approach this --

The aircraft and its components only become energized when

1. Battery 1 or Battery 2 is turned on
2. Ext pwr is on
3. APU is on

There will be certain items on the flight deck which will also only turn on under these conditions, such as the rudder trim, MCDU, ATC/TCAS, etc.

I would assume the most straight forward way to implement a power on state when either condition 1, 2, 3 is satisfied is by using a relay.

However I would need a 'energized' state of the aircraft logic to output to the relay (it only turns on when either condition 1,2 or 3 is satisfied).

Is there an FSUIPC offset which can only output to the relay boards when the aircraft is in an energized state, or is there another method you would recommend to implement these features?

In my current cockpit build for example, the aircraft rudder trim panel is always on the 'on state' (28 VDC supplied). However I only want power to be supplied to the panel when the criteria above is fulfilled.

Thank you.

Ben

[spiliot]

Shouldn't a logic board that is powered when the FS computer is on, be able to handle that relay without depending on any other aircraft system? In that case all that is left is reading the proper offsets. Unless I'm missing something...

[iwik]

Hi Ben,
If i read you correctly, you would like to drive a relay when ANY ONE of the above are on. Then just take the output that lights the LED in the switch to drive a transistor and your relay.
Les

[OmniAtlas]

Shouldn't a logic board that is powered when the FS computer is on, be able to handle that relay without depending on any other aircraft system? In that case all that is left is reading the proper offsets. Unless I'm missing something...

Hi spiliot -- the FS computer will always be on. However I only want the systems to power up when battery, ext pwr, or apu is on, as like in the real aircraft.

For example at this time I have 28 VDC supplied to the rudder trim. The LCD remains on even when the aircraft is not on an energized state ("cold and dark"). This is unrealistic.

[OmniAtlas]

Hi Ben,
If i read you correctly, you would like to drive a relay when ANY ONE of the above are on. Then just take the output that lights the LED in the switch to drive a transistor and your relay.
Les

Hi wik, yes you are correct, I will attempt to use one of the output light assignment to drive the 28 V power relay.

For example, I will use a Battery 1 output to turn on the power supply for the trim.

Is it possible to use "OR" logic for the relay?

For example --

If "Battery 1 output = 1", OR "Battery 2 output = 1", OR "EXT PWR= 1", or "APU =1" THEN "RELAY SWITCH = 1"

[iwik]

Yes, that's the way to go in logic. Can also be done in hardware with a Exclusive Or gate. Take the three outputs and then Output of the gate will only be "1" when ONLY 1 of the inputs is a 1.
Les

[cmdr114b]

Yes, that's the way to go in logic. Can also be done in hardware with a Or gate. Take the three outputs and then Output of the gate will only be "1" when ONLY 1 of the inputs is a 1.
Les

What about taking an output from each lamp via a diode (each connected to the Anode of a diode) then join the three Cathodes together (as a diode OR) and they would drive a relay coil via a transistor. Don't forget to put a diode across the coil of the relay to prevent back EMF.
John

[OmniAtlas]

I'm not too much of an electronic expertise here so will be looking for the most straight forward implementation -- I don't think I can program software to do the action. Simon our cockpit builder friend has been able to implement these functions using SIOC.

If we were using an adruino relay, (one of these http://arduinobasics.blogspot.com.au/2014/09/relay-module.html ),

Can I just wire the FDS I/O board LED outputs to one of the adruino relay inputs?

For example the BATTERY 1, Battery 2, Ext Pwr, APU, (perhaps also when ENG1 sw is on, and ENG2) output directly wired together to one relay switch this would satisfy the "OR" criteria?

Thanks

[iwik]

Ben,
Any relay module can be used. you cannot just connect the outputs of the FDS board to relay module. Each output must be isolated like John said using a Diode between the output of the FDS board and the input of the Relay module. Anode to FDS and cathode to relay module.
now we must differentiate between an " OR " gate(like a simple diode one) and an " Exclusive OR ".
A diode " OR " will allow more than ! OUTPUT which is high at any time to operate the relay.
An " Exclusive OR " will only allow 1 input at a time to OUTPUT a 1. Should two switches be on at the same time then the relay will not operate.
So you have to first decide if you only want 1 switch to be on and the relay to operate. I am not up with the A320 operation so not sure what your switch combo logic has to be.
You say there is a SIOC script written then there should be an output defined to meet the ' OR " conditions this output simply is connected to the relay module input and should operate according to the script.
Hope this helps.
Les

[OmniAtlas]

Thanks Les -- do you have any experience with the OC relay card?

http://www.opencockpits.com/catalog/relays-card-p-61.html?cPath=21_38

It seems like it may be able to do the functions I would like with minimal fuss.

It can connect directly to the computer (drawing 5v), and SIOC scripts can be used to activate the relay. Is SIOC able to read FSUIPC offsets?

There will be several functions I would like to implement with the relay.

When the aircraft is energized (by battery, APU, engine power, or ext power), power will be supplied to the following components:

1. ATC/TCAS
2. Rudder Trim
3. Weather radar
4. RMP
5. ACP
6. Clock
7. FCU
8. VOR/DME

That seems like quite a fair few....perhaps I should just hook up all the components to the corresponding 28 VDC power unit, and use the relay to turn on the power unit, instead of individually wiring the relay to the components.

In addition 28 V supply will be required for the A/P solenoid lock on the sidesticks - this will only turn on when autopilot is enabled, and a relay will have to drive this.

Hopefully all of this can be performed with the OC relay card?

The other alternative is the FDS-SYS-R1X card -- I believe this uses the Tekworkx interface software which has a GUI for entering the FSUIPC offsets and may be easier to use. The board however is more than $200 more than the OC relay card.

http://www.flightdecksolutions.com/components/interface-it/fds-sys-r1x/

[iwik]

Ben,
The o/c relay card would do the trick alright. It handles offsets fine . The catch is learning SIOC. It can be a bit of a learning curve but very handy. i am no expert at it and struggle when ever i have to use it. When it comes to wanting to do things like you are finding out needed it sure is an advantage. Everything comes at a price.
The FDS card is the way to go to avoid this but as you point out it cost dearly because they have done all the hard work.
It might pay for you to have a look at what you might like to do in the future and consider
learning it. As something like this affords you great flexibility as i have found out.
If you can keep your requirements simple then sioc can be reasonably easy to use. There are
plenty of examples out there. Others on this site have been very helpful to me when in difficulty.
Les

[OmniAtlas]

Thanks Les -- Simon has his whole setup with SIOC, so I will need to have a good chat with him about the scripts.

I will place an order for the OC relay; actually more excited in using it for the sidesticks and A/P solenoid lock.

Any idea if a diode is needed for OC to prevent EMF, or are they built in?

Regards.

Ben

[iwik]

Ben,
The diode john was talking about will be on the pcb so not needed.

On an unrelated point, i read that you will in the future add more pc's to your mix. Did'nt you have more and decided you wanted less hassle .What has happened to change your mind.
Les

[OmniAtlas]

Cheers Les, I will place an order for the OC boards this evening.

At this stage I am happy with running on one computer, however I do lose about ~10 frames, which becomes quite noticeable when I am flying into commercial payware airports. When I have the space to setup 2 or 3 projectors it will be impossible (well not very fun) to run off one computer.

I have also noticed the ND/PFD lags if they are not in focus -- you will need to click on the windows to bring back smooth speed. Hopefully this can be eliminated if they run on a separate system.

I will probably try and purchase one of those second hand Dells on the ebay market and stick in a cheap video card, one with lots of ports.

Will need at least 5 video outputs (PFD/ND, MCDU).

[iwik]

Thanks Ben,
I am hoping to get onto the A320 shortly so was curious. Have fun
Les

[Knoepflesdruecker]

Very interesting Thread! I will surely need this information in the future, too. Thanks to all of you!
Best regards,
Marco

[Fritz]

Hello Ben,

I use an OC relay card, which turns on the power supply of individual components:
Bat1 switches the power supply for Cpt, FO and EWD/SD monitor and Bat2 switches the power supply
for the background lighting as well as Boddy Shaker.

Originally, I had the idea that Bat1 and Bat2 turns on the power of the computer, then the
Programs should starts by autostart. Didn't get this to work correctly, since the program also need to starts in a certain
Order. Here is a program necessary to do this.

[OmniAtlas]

Thank you Fritz. I'm putting off on the OC relay card, doing my research with Simulator Solutions Simstack cards first - they maybe able to perform relay functions in addition to providing the correct amperage required for genuine panels at +5v.

[OmniAtlas]

Hi all - just an update on the solenoid - this was successfully implemented using Arduino's, Mobiflight and the Arduino Solenoid relay.

This was the first time I am using arduino and mobiflight and I am pretty impressed. So impressed in fact that I am in the process of designing a shield to help with one critical aspect of the simulator (no solution in the market is available so far) - more on this later.

The schematics and logic for the solenoid can be found here - https://soarbywire.wordpress.com/2017/11/13/sidestick-solenoid-lock/

The next step is going to figure out which offsets activate the aircraft power on state. Mobiflight allows != or 'NOT' states. The published offsets by Jean Luc have the following which would be useful:

Offset 7396 (byte 3 - Battery 1, and byte -5 Battery 2 off states)
Offset 7397 (byte 7 - Elec Ext Pwr Avail)
Offset 7397 (Byte 5 - Elec APU Gen OFF)
Offset 7398 (byte 1 - Rat & Emerg Gen Fault)

Using these offsets we can program the aircraft to turn on systems using simple logic.

Is anyone familiar which systems are activated when battery 1 or 2 is turned on?

For example (and I have to double check), only the overhead flood lights turn on with battery 1 and/or 2.

Integral (panel backlight) lighting is only turned on with ext pwr, elec apu on.

When would the trim display, FCU, ATC/TCAS, weather, clock systems power on?

[cmdr114b]

I have written a little app to turn ON/OFF the ground power over the network which some might find useful.

You can download it from here http://www.fda-engineering.co.uk/GNDPWRConnect.exe
John

[OmniAtlas]

Thanks John -- this will be helpful on a remote, iOS computer, when we don't have access to the P3D menu.

I'll add it to the list of programs / resource section.

[cmdr114b]

My pleasure.

In case you don't know this already and I should have said, it uses FSUIPC so you need WideClient for it to work.

Happy New Year to everyone.
John