SYS Card Wiring help request (Resolved)

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SYS Card Wiring help request (Resolved)

Post by Luisg »

I purchased the SYS1X and I am trying to wire my overhead panel. This is my first project, so all the help with be much appreciated.

I have read the manual and it mentions purple wire/blue wire for switches/rotaries and Red/Black for LEDS.

So I can understand it better, the purple wires goes connected to the center or the blue wire? I have 8 purple and 1 blue.

As for the LED's, the cables I received are 8 white and 1 black. Do i just do the same even though they are different colors as stated in the manual?


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Post by Fred »

The color of the wires do not really matter. However it is best to be consistent (i.e., use the same color) for LEDs and switches respectively. This is to avoid plugging an LED wiring harness into a switch header receptacle and vice versa. That is the main thing you want to be careful about. With all those wires it is easy to get them confused! The odd (single) color wire in each harness is for the "common" wiring lead.

Yes...In an ON-OFF-ON kind of switch the common wire is connected to the center pole (in your case it is the blue wire which gets daisy-chained with the other switches in that group). For a simple ON-OFF switch it does not matter since you can invert the on/off state via the software, but it is best to install and wire your switches consistently to maintain your sanity!

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Post by GDR »


As Fred stated, the color doesn't matter. But be consistent.

In your example (for LEDs), you have 8 white and 1 black wire.
So, this means that you can connect 8 LEDs in serie with black as common.
Have a look at the schema I have made to clarify the wiring.

Note that a Dim/Bright annun needs to be on the same segment since the annun uses two output states using the same common.

The same for the switches. ... _Print.pdf

Hope this helps you further.

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Post by Luisg »

Thanks guys for your help. I wasn't to sure about the daisy chain, but now I have to toggle switches showing up on the software. I'll leave the LED for last.

Thank you.


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Thank you!

Post by pcos »

Thank you everyone for jumping in!
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Post by vidarf »

Here's an image from my overhead:


It's all white wires, but that is because I had to extend the wires that came with the SYS boards for my needs. The black wires are the common for each group. Shown in the image is the back of the fuel pumps panel. It has 7 switch inputs (the last goes to another switch on the overhead, do not remember which). You might just be able to trace the route from left to right on the switches, up to the center tank switches in the middle and finally to the cross feed switch.

The same goes for the LED's. As you can see, I've written "B+" next to the annunciator above the cross feed switch. That annunciator has two states. I reserved output #7 and #8 on ALL output groups for this feature. Output #7 is the bright state, and #8 goes through a resistor board I made, for the DIM state. The YELLOW wires comes from that resistor board and corresponds to output #8 on the group. I was able to "group" a dual state / blue annunciator with neighboring "normal" annunciator, except for two. Since the SYS card has more outputs than I need, I used two output groups just for those two annunciators.

Here's the resistor board:


In hindsight, I could've saved wire by altering the design on that board by wiring #7 and #8 from the SYS card through the resistor board, then one wire to the annunciator. Oh well.

This approach gives you 6 output per group for all other colors, but that is more than enough.

Shown in the last picture, you'll see the different colors used. Red for switches, white for annunciators. NB: I have the first version of SYS cards.

More on my story here.

The best method I found for daisy-chaining switches, is to use sold-core wires. The wires that comes with the SYS cards is "stranded" and flexible. I used stiff wire, which is MUCH easier to work with since it more or less keep any bends or hooks you make.
Reffering to the first picture: I made a piece of wire long enough to run between two switches. I then fed the wire coming from the SYS board into the hole in the solder point of the first switch where the small piece already was inserted, then soldered that switch. I then moved to the next switch, made another piece of wire going between switch #2 and #3, soldered switch #2. This made the process easier. In some areas I had to solder 3 wires to one switch simultaneously, and this approach made that MUCH easier to do!

I then connected the red wires (white extension though...) to their respective switches. Finally, I used a multimeter with short detection mode (it beeps if there's a short between two points) to check that all the common wires was connected. I then checked that there was no shorts between the solder points on each switch. By doing this, the overhead worked without any errors.

You do not need to keep track of which switch or output is connected to where. That's the beauty of the SYS cards! The detection mode is an extremely nice feature!

One thing though - I marked the connectors on the SYS cards with the first output number of that group. Should you ever need to disconnect everything from the card(s), you know which connector goes where. That's the only thing you really need to keep track on.

Hopefully this practical example can help you and anybody else wondering about how to do this. It may not be the best way, but it works. :)

The SYS cards are very powerful and extremely user-friendly, that's for sure! I am going to use the SYS relays cards when I get around to make the start switches!

Peter, a SYS encoders card would be VERY much appreciated! Just because I am a detail "nut" and would love to interface and simulate as much as possible. LAV light kind of thing, but still...

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