# Need help identifying sprinkler controller wires



## djlandkpl (Jan 29, 2013)

Beardown34 said:


> The larger bundle carries all the multicolored wires that plug into stations 1-7, as well as 1 white wire, which is plugged into "COM" at the very bottom -- common wire I'm assuming. This bundle also carries a black and a grey cable that are plugged into two separate terminals each marked "SEN", which is for a rain/weather sensor. There are also 3 unused wires that remain unstripped.


The wires connected to 1 -7 and COM would transfer to your new controller the same way. 

Take a look in your valve box(es) to see if black and grey are in the bundle and if they are connected to anything. 




Beardown34 said:


> The smaller bundle has just two wires -- 1 white one, which is also plugged into "COM" at the bottom, and 1 red one, which is not attached to anything.
> 
> I'm trying to figure out what that red wire is for -- especially since the end is stripped, which makes me think it was used for something in the past, and is supposed to be plugged in somewhere.
> 
> This got me to looking around the outside of the house, where I found a cut wire bundle, with just a white and red cable inside. Next to it was a Rain Bird Rain Check shutoff sensor.


Additionally for the black and gray wires as well as the red/white combo you can do a continuity test if you have a multimeter. Disconnect the wires from the controller and connect them together black to gray and separately red to white. Go to the other ends and put your multimeter leads on the wires. If you have continuity then you have the right wires and you will be able to figure out what they do. 

If you switch the controller off of bypass does it stop working?


----------



## Beardown34 (Aug 23, 2017)

Thanks -- will check it out


----------



## Beardown34 (Aug 23, 2017)

Yes if I take it off bypass, the controller says SEN OFF and the system doesn't run.

OK I left the wall controller on. I inserted the Red + White into the two SEN terminals. I went to the yard where the cut wire is, and touched the multimeter to the Red + White. No voltage, even if I flipped the black/red leads of my multimeter. 

I then put the Grey + Black wires into the two SEN terminals (ie. the original configuration). Went out to the yard to the cut wire, and touched the multimeter to the Red + White. The voltage bounced around 24-28V.

Soooo I guess this indicates that the Red + White of the cut wire is continuous with the Grey + Black in my controller box?

And what might the unattached Red wire in my controller box be then? And what would the white common wire that comes with it be for?











** Also, how can I tell if I have a master valve in my system or not? Is it something visible in my basement, where the water supply and RPZ are?











** Also, what is this box for in my basement? Someone told me it's a booster pump? But it's disconnected ... yet my sprinkler system still works.











Thanks for all the help!!


----------



## djlandkpl (Jan 29, 2013)

If you have a master valve, you'll find another valve somewhere that is in the water line before your other valves. 

I don't know anything about the pump. Just a guess that the red/white pair were used to trigger the pump.


----------



## Msradell (Sep 1, 2011)

If your system is working fine without the pump turned on there's no need for it. It's quite possible that when the system was installed the water pressure in your area with lower but since then work is been done on the system that raise your incoming pressure. In most areas city water pressure is sufficient to run sprinkler system without the need for booster pumps.

As far as the wiring goes it sounds like your well on the way to fix that problem, hope it all goes well.


----------



## Beardown34 (Aug 23, 2017)

The cut wire in my yard has a red + white cable. I'm guessing the white cable is the common wire right?

But according to my continuity test, the wires in my controller box that create continuity are the grey and black cables attached to SEN. Is one of those two supposed to be a common wire?

I ask because there are already two white wires in my controller box, hooked up to the COM terminal. One white wire from the large bundle with the zone 1-7 wires. The other white wire is bundled with a Red wire, but as stated above, according to my continuity test, it doesn't seem to be continuous with the Red + White cut wire in my yard, despite looking the same.


----------



## Beardown34 (Aug 23, 2017)

djlandkpl said:


> If you have a master valve, you'll find another valve somewhere that is in the water line before your other valves.
> 
> I don't know anything about the pump. Just a guess that the red/white pair were used to trigger the pump.


Is the master valve something I'll be able to physically see in my basement?

Or "in the water line before your other valves" meaning somewhere buried in-ground?


----------



## djlandkpl (Jan 29, 2013)

Beardown34 said:


> The cut wire in my yard has a red + white cable. I'm guessing the white cable is the common wire right?
> 
> But according to my continuity test, the wires in my controller box that create continuity are the grey and black cables attached to SEN. Is one of those two supposed to be a common wire?
> 
> I ask because there are already two white wires in my controller box, hooked up to the COM terminal. One white wire from the large bundle with the zone 1-7 wires. The other white wire is bundled with a Red wire, but as stated above, according to my continuity test, it doesn't seem to be continuous with the Red + White cut wire in my yard, despite looking the same.


Any way to trace where the wire runs in/along the house. My guess is that it may have been used for the rain sensor and then abandoned. Try disconnecting the white from the COM terminal and see if anything stops working.


----------



## djlandkpl (Jan 29, 2013)

Beardown34 said:


> Is the master valve something I'll be able to physically see in my basement?
> 
> Or "in the water line before your other valves" meaning somewhere buried in-ground?


If you have a master valve it could be anywhere but it would be before your other valves. The master valve is designed to stop water flow to your entire system in case one of the zone valves fails. 
Since your system is working, I doubt you have a master valve.


----------



## Beardown34 (Aug 23, 2017)

These are great points djandkpl!

So most master valves are normally off?

Meaning if I have a master valve in my system, but someone forgot to wire it to power in the controller (or wired it incorrectly, or the wires got cut-- point being no power to the master valve), then the valve would stay closed and I would have no water coming out of the zones?

If this is the case, then I feel confident my system DOESN'T have a master valve, because my irrigation works even though nothing is plugged into the P/MV terminal on my controller. 

That's also a good troubleshooting technique with the common wire. I have two wires going into my COM terminal. One of them is bundled with the multicolor wires from my watering zones. So if I disconnect that one, my watering zones should stop working?

And if I disconnect the other white wire ... I'm guessing nothing's going to stop working. The rain sensor wire is cut, and the system is on bypass. I don't know what else an extra common wire would be controlling. Unless it has something to do with that blue pump in my basement ... ("booster pump"?)


----------



## djlandkpl (Jan 29, 2013)

Correct about the master valve. My guess is the white/red pair were used at some point but abandoned. If for some reason it's being used as a common for a zone, that zone will stop working. 

See if you can find a red/white cable near the pump. That might solve the mystery.


----------



## Beardown34 (Aug 23, 2017)

djlandkpl said:


> Correct about the master valve. My guess is the white/red pair were used at some point but abandoned. If for some reason it's being used as a common for a zone, that zone will stop working.
> 
> See if you can find a red/white cable near the pump. That might solve the mystery.


Ok then considering nothing in the controller box is wired in the P/MV terminal yet my irrigation works, I feel confident I do not have a master valve in my system. 

Regarding the grey and black cables in the two SEN terminals, that are continuous with the cut red/white cable in my yard -- is it possible that red cable for connected or spliced somewhere to become two cables? Meaning the 1 red cable became both the black and grey? I ask because I'm wondering if one of the black and grey is the common wire for what was the rain sensor, or if the other unaccounted for white wire in my COM terminal is the common wire for what was my rain sensor.


----------



## djlandkpl (Jan 29, 2013)

Beardown34 said:


> Ok then considering nothing in the controller box is wired in the P/MV terminal yet my irrigation works, I feel confident I do not have a master valve in my system.
> 
> Regarding the grey and black cables in the two SEN terminals, that are continuous with the cut red/white cable in my yard -- is it possible that red cable for connected or spliced somewhere to become two cables? Meaning the 1 red cable became both the black and grey? I ask because I'm wondering if one of the black and grey is the common wire for what was the rain sensor, or if the other unaccounted for white wire in my COM terminal is the common wire for what was my rain sensor.




You would need to do a continuity test to test your theory. My system has 6 valve boxes and 3 junctions where wires join and colors change. Anything is possible...


----------

