Aprilaire Model No. 50 Current Sensing Relay 24VAC 12W Humidifier Part

You will find that the Emergency Stop Module gives you a reliable way to halt operations quickly.

You will find that the protection relay is easy to test, which helps you verify safe operation before going live.

In the specs, the model is listed as Not Applicable, which seems practical for broad relay selections.

Another benefit is that the RS-1M mates well with common sockets and headers.