16 zone Iro requires 2 common wires?

Hi. I will be hooking up my 9-zone (+1 master valve) irrigation system to a 16-zone Iro soon. I have:

  • wire for master valve
  • wire for each zone (1-9)
  • a single common wire
  • two wires from external rain sensor

Looking at this diagram, it’s pretty clear where everything goes except for the common wire. Can I plug in my single common wire to the left common terminal (while still using zones 1-9), or will I have to put a pigtail on my common wire so that I can connect my single common wire to both common terminals on the Iro?


Hi @ramblinwreck,

Good afternoon. Sorry for any confusion on the common wire. You only need to connect the common to one of the two white terminals. No need to pigtail to both.

Is the rain sensor wired or wireless?

Best, Emil

Thanks @emil.

Regarding the rain sensor, I’m using this wired (normally closed) rain sensor:

On a slightly related subject, I’ll shortly be installing a 16 zone Iro to replace two existing controllers. Would I be correct in assuming that I could connect the common from the first group of valves to the first bank of connectors, and the common from the second group of valves to the second bank?


yes, this will work.

Thanks for the confirmation. When my 150’ of sprinkler wire comes in, I’ll hook up the second bank that way.

@ramblinwreck – not sure if you still need help with the Orbit rain sensor, but since it’s wired it’s a very simple installation. Please see this support article :smile:

@kelpayne – Yes, as @plainsane mentioned this will work. Will you be using all 16 zones? For reference, here is the Iro wallmount wiring diagram.

Hope this helps!

Hi @emil, no, sorry I wasn’t clear – it was pretty obvious how to hook up the Orbit 57069 rain sensor (2 wires, 2 terminals). :slight_smile:
I was only unsure about the two common terminals until you explained it. I ended up using the right side common terminal (only) and it works fine.

By the way, I really like getting the rain sensor trigger notifications on my phone. Besides the obvious geek factor, having this recorded in the Iro’s history is actually useful because it helps me tune the duration adjustment on the sensor (a movable window that controls how quickly the internal discs dry out)…

Hi @ramblinwreck,

I assumed so, but just wanted to double check :blush:

That’s a great point. I hadn’t thought of using it for that before now, but thanks for sharing. I’m sure others could benefit from this.

For anyone that doesn’t know what the duration adjustment on the sensor (a movable window that controls how quickly the internal discs dry out means, most sensors have a twisty collar at the base that either covers up or reveals the air vent, adjusting the speed of drying time and return to normal watering.