The RP-V has a built-in isolated power supply designed to accommodate a nominal operating voltage of 24 VAC at 50/60 Hz input power.
The built-in power supply is based on a full-wave rectified, isolated design, which is complemented with electronic protection components for transient protection, overload protection, and EMC compliance.
To power the controller, use a Class 2 (EN 60742) transformer supplying a nominal 24 VAC at 50/60 Hz. For more information, see RP-V Controllers .
The 24 VAC power input (L and N) is galvanically isolated from the electronics. This minimizes the risk of damage due to earth currents and permits the input power to be wired without concern for polarity matching.
With the isolated 24 VAC power input, you can use a central transformer for many RP-Vs, instead of one transformer for each RP-V, to reduce installation costs.