Tutorial Cheap & cheerful Dyadic SCN5/6 to rs485 wiring

Having received my rs485 converters, I needed a way to wire from the actuators communication plug to the converter. There's already an excellent SCN5/6 wiring tutorial on this site so I won't get into the wiring but it's basically matching up the GND, POSITIVE and NEGATIVE pins to the corresponding GND, + and - on the RS485 adapter. You don't need to worry about the forth pinout (+5v) as it's not needed.

I didn't want to cut into my stock communications cable so I priced out some extension cables. These would have the proper molex plug and bare wires I need on the other. The issue was however cost. The best price I could find was $45. USD each. Times 3 units plus shipping I was looking at close to $200. Cdn with the exchange rate, TAXES and import duties. No thank you!

So I decided to see what I could devise myself. I knew I had to go from male pins to bare wire. How to attach wires to the pins on the actuator cable? It would have to be a reasonably solid and reliable connection too.

Here are the pins on the communications cable:





Looking through my drawer of misc cables I happened upon a CD-ROM audio cable. I had a couple of these leftover from builds years ago.



I realized the connectors on each end were female and about the right size to fit over the cable pins. First I cut the cable in half. This would give me 2 cables for 2 actuators (axis).



I would then need to strip off the old shrink wrap. Some cables might not need this step.





On the 'cut end' of each cable, remove about an inch of the outer insulation to expose the wires inside.



Trim about 1/3 of an inch off the RED and BLACK wires. The GND cable is bare and doesn't require trimming.

Next it's time to remove the female connectors from the plastic plug. I used a magnifying glass and a darning needle to push the tabs in on each connector. After doing this for each wire they slide right out of the plastic plug.

NOTE: Some gentle pressure is required however don't pull too hard. If you have to it means the release tab isn't pressed enough. Pulling hard on the cable could damage it. Try pressing the tab down again while pulling gently.



You will end up with 2 cables like this.



Next attach the wires to the pins on the actuator cable by gently pressing the female connectors over each corresponding pin. They should fit snugly. If one feels too loose you can always GENTLY crimp the female end a little and try again until it feels snug. Do not over-crimp as you won't be able to get the female connector over the pin making the whole cable useless!

You should end up with this:



To make this connection even more secure you could try a dab of hot glue and some shrink tubing or tape.

Next wire the other end of the cable to the rs485 adapter. Most of these adapters have screw down terminals making the connections very secure.




Connect the rs485 adapter to your PC with a USB cable and you're done. You've wired an actuator with something you just had lying around For each actuator (axis) rinse and repeat.

I hope someone finds this tip useful.

Cheers,

DaV

Thanks for the tip! I was wondering how i was going to connect my scn5 acuators. Now I will do just as you have shown. thanks!

Hey glad to be of help! That's what it's all about.. sharing info so it's easier for the next guy right?

.. And thanks for the note

Cheers,

DaV

Could you tell me which rs485 adapters you purchased and what it cost and where it was purchased? Im in Ontario Canada and as you know purchasing across the boarded is very expensive at the moment. thx

[QUOTE="To make this connection even more secure you could try a dab of hot glue and some shrink tubing or tape.

Next wire the other end of the cable to the rs485 adapter. Most of these adapters have screw down terminals making the connections very secure.

27366

Connect the rs485 adapter to your PC with a USB cable and you're done. You've wired an actuator with something you just had lying around For each actuator (axis) rinse and repeat.

I hope someone finds this tip useful.

Cheers,

DaV[/QUOTE]

FYI......Not sure if it makes any difference in what your doing but it might confuse some. I was taught that red was always positive and in the last pic illustration you have the plug marked for a ground wire, and then you have red to -, and a black to + which is backwards I beleive.

Hi Harold,

Always nice to hear from a fellow Canuk Here is the link to all the info you need. I had good luck with both of these and the cost was reasonable.. even with our crappy dollar ATM.

http://www.xsimulator.net/community/threads/scn5-wiring-tutorial.5566/page-2#post-95409

Cheers,

DaV

FYI......Not sure if it makes any difference in what your doing but it might confuse some. I was taught that red was always positive and in the last pic illustration you have the plug marked for a ground wire, and then you have red to -, and a black to + which is backwards I beleive.[/QUOTE]


Hi Hobbs,

Lol You are right. I was wondering when someone was going to notice that! Actually, I initially labelled the RS485 module wrong. Red is in fact positive and black negative. The wiring is correct but my labelling is wrong in the pic. The others I did were labelled correctly but of course I took a photo of the mislabelled one

Hopefully this will clear up any confusion. Of course it doesn't matter what color wire is connected to what, as long as they connected to the same polarity on both ends, but your point is a 'best practice' for sure.

Cheers,

DaV

Hi Hobbs,

Lol You are right. I was wondering when someone was going to notice that! Actually, I initially labelled the RS485 module wrong. Red is in fact positive and black negative. The wiring is correct but my labelling is wrong in the pic. The others I did were labelled correctly but of course I took a photo of the mislabelled one

Hopefully this will clear up any confusion. Of course it doesn't matter what color wire is connected to what, as long as they connected to the same polarity on both ends, but your point is a 'best practice' for sure.

Cheers,

DaV[/QUOTE]

Lol....I kinda figured it was one or the other.....just thought I would bring it to your attention. Maybe you could just edit the +,- signs on the pic.

Probably easier to take another pic and upload it. Will do that over the weekend

Cheers,

DaV

Lol....I kinda figured it was one or the other.....just thought I would bring it to your attention. Maybe you could just edit the +,- signs on the pic. [/QUOTE]

Apologies.. I haven't been on in awhile. Too busy playing with my DK2

I finally got around to editing the pic in question. The polarities show correct now. I'm really glad some folks are finding this useful!

Cheers,

DaV