remote Zone extender

[vinthewrench]

Ray;

I would like to reach some additional zones about 60′ way from the controller. I was considering using the Zone extender and making a custom cable between the main unit and the Zone extender. How far can I run the cable between the main unit and the zone extender?

background.

Ultimately I would like to drive three or four linear actuators. I would H-bridge them in the standard way and have the open sprinkler logic treat the bridge as valves.that way I only need two zones for each actuator. my problem is I already have a standard garden relay 7 wire cable in place, and am trying to avoid pulling a new underground wire. placing the zone extender on the other side of the cable from the main unit is an attractive idea, but I am not clear what signals you are running on that ribbon cable?.

[Ray]

60′ is probably ok. You can make a custom cable using a long Ethernet cable. We don’t have any test data on how far the cable can run — this depends a lot on for example, the wire thickness. So I can’t say for sure, but I think 60′ sounds ok.

The signals running on the ribbon cable are I2C (if you are referring to OS3) and shift register (basically SPI bitbang) data for OS 2.x or OSPi. These are not direct on/off signals.

[vinthewrench]

Ray – What are the pinouts for the DC zone expansion 3.0 board.. I see that you are using a 10 pin connector, and the diagrams on Github are for 2.0 with a 8 pin connector. I am going to try and get it to run over a remote cable but I only have a 7 wire cable in place.. that should work., since AFAIK I only need to run the GND, VCC, DAT,CLK,LAT,NOE – did I miss something?

thx

[Ray]

On the DC controller and expander, only 6 (in fact, technically only 5) wires are used out of the 10-pin cable. The Eagle design files of all versions are in github, maybe you were looking at the wrong github, but the correct link is here:
https://github.com/OpenSprinkler/OpenSprinkler-Hardware/tree/master/OS/3.0/DC_driver
I’ve attached two images showing the 10-pin connector on the controller, and also on the expander, so you can figure out exactly which pins are used, and the ordering of pins. When I say ‘technically 5’ I mean the DCG (DC ground return) occupies 2 of the pins, so technically if you are short of wires you can just use either one of them.

Please note that in contract to expander 2.x, expander 3.0 uses I2C, so there is no DAT, CLK, LAT, NOE etc., instead, it has SDA, SCL.

Attachments:

1. 

   os32dcdr_extconn.png
   

2. 

   os30extdc_conn.png
   

[vinthewrench]

thank you Ray — you are awesome

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