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Dear forum users,
i have a question regarding the connection of sprinklers to the processing unit: Somewhere in the forum i have read that can be used the cables used for ethernet.
It is not clear if they are used in order to bring the internet connection to the unit, or also for the connection of sprinklers to the unit.
In case they are also for connecting the sprinklers, what kind of rules have to be followed? for example are they resistant to water (ip65)?
While I guess it is *possible* I’m wrong and someone posted somewhere to use CAT cable for wiring up the sprinklers… I’m sure you must have misread it. You really need to use direct burial rated wire.
Some people have used Ethernet cable for wiring sprinkler valves. It’s not really recommended because Ethernet cable wires are pretty thin and are not suitable for running high current. However, typical sprinkler valves only draw about 250mA when activated, which is not a high amount of current. So I suppose in practice it should be fine to use Ethernet cable.
Above ground and indoors, sure. I presumed the author meant typical CAT cabling. There is ethernet cable that is rated for outdoor and burial,and that should be suitable (but probably more expensive than sprinkler wire anyway).
I guess it depends on the application. Of course, purely from a point of view of electricity traversal, wire is wire is wire… if it can handle the current, then it really doesn’t matter if, for example, you’re just temporarily hooking it up for testing or if you’re housing the valves indoors. But if you’re doing a “normal” sprinkler install, then why go through the trouble of trenching and backfilling just to have to do it again because rocks have rubbed or insects/animals have eaten through the sheathing? Corrosion, thermal stability, flexibility of the core within the insulation… it all plays a role when doing an outdoor and (especially) subterranean installation.
Just for some reference: http://en.wikipedia.org/wiki/Direct-buried_cable
Thanks for the answers.
I meant really ethernet cables, as stated in the following post that i have found again.
https://opensprinkler.com/forums/topic/adjusting-output-voltage/
Anyone tried this approach?
What “approach”? That thread just mentions that he is insisting on using (imho) inappropriate cabling for his installation, recognizing that the under-sized wires will result in significant voltage drop due to distance, and wondering if it would work. The bulk of the discussion is about a mismatch between theory and practice w.r.t. voltage drop calculations.
And what is “really ethernet cables”? “Ethernet” is just the usage, not the specification. It really has little to do with the wires themselves, but rather the sheathing and physical properties associated with the cable as a whole.
Do you have a REASON for wanting to use non-standard cabling? You really haven’t given enough information to provide advice. You hinted originally, since you asked about waterproofing, that it is an outdoor installation (although perhaps you’re just concerned about potential leaks at the valve – which is certainly something to be concerned about!). Using indoor rated cable in an outdoor situation – especially buried – is asking for trouble.
If you just want to know if it is electrically possible… Ray gave you the answer. If you want to know if it is a good idea… give us more details or accept my answer and go buy the right cable for the job.
Hi Steven,
you are right, it is better to provide more details about my actual setup in order to have suggestions.
At the moment I have a Claber unit that is positioned outside my home, more or less at 15 meters from the building, and that unit receives just one cable with 220 power (less than 1 centimeter of diameter).
This unit is located inside an ip65 container, and is linked to 5 valves that are positioned at 1 meter from the unit, using original cables bundled with valves.
Due to the fact that I’m moving to OpenSprinkler, I have some doubts that the external positioning is safe (especially for robbers), so I would like to install the new OS unit in my house, bringing only the connection to the external valves.
Having a lot of connections from the building to valves, around 15 + 1 meters, requires too much space in the grounded container of cables, so I have thought that replacing the existing power cable with an UTP cable (having more or less the same diameter) will be easily managed, and should allow me to control up to 7 sprinklers (if working of course).
If by “grounded container of cables” you mean that you have conduit (pipe) running the entire distance… then you’re probably OK. The conduit should provide protection for the UTP cable. Plus, if there is a failure down the road, you can try again with minimal problems (ie. you don’t have to dig a trench again). So if that’s the case, if you want to try UTP cable then go ahead.
However, if the conduit isn’t sealed (or if I misunderstood and you don’t have conduit), you still may have issues with water ingress, soil acidity, and thermal flexing. So I’d still recommend proper cable. 8 conductor direct-burial sprinkler wire isn’t a whole lot thicker than UTP. Certainly it is less than 1 cm diameter. You don’t need 8 individual single-conductor direct-burial cables!
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