Green roof project with irrigation system. 24 VAC wiring requirement.

[victor.cherkashi]

I have green roof project in NYC, above 11th floor. The roof will have an irrigation controller Pro-C Controller by Hunter Industries Incorporated (https://www.hunterindustries.com/irrigation-product/controllers/pro-cr).

Transformer output is 24 VAC and 1A (from controller to control valves). The spec doesn’t mention any circuit class 1/2/3.



My assumption is that I should use article 720 (from controller to 24 VAC control valves).

a. Cable can be only 2 wires (no ground).

b. Cable should be sunlight resistant and for wet locations.

c. Conduit is not mandatory required.

d. 720.4 Conductors. Conductors shall not be smaller than 12 AWG copper.

e. 720.11 Cables shall be supported by the building structure in such a manner that the cable will not be damaged by normal building use.



Did I miss something?

 

[hbiss]

This is just a simple lawn irrigation system that anybody from the burbs would know about and have.

The Pro-C controller uses an external plug-in 24VAC transformer that is CL2 which powers the controller. The controller interconnects with the valves. You can use 18/2 thermostat wire from the transformer to controller.

Use regular irrigation multi-conductor cable that's made for interconnecting the Pro-C and irrigation valves. It's sunlight resistant and suitable for direct burial. It is not, however listed for use within buildings. The Pro-C can be had in an outdoor version.

No need for any of that 720 stuff.

-Hal