What is the switching arrangement on a Robertshaw EA thermostat?

The Robertshaw EA thermostat utilizes a single-pole, single-throw (SPST) switching arrangement. This means that the thermostat has one switch that can either open or close a single circuit, allowing it to turn the connected device on or off. This design is straightforward and effective for basic temperature control applications. The simplicity of SPST switches makes them a common choice in thermostats where the functionality is limited to controlling one heating or cooling device based on the temperature set point.

Other options involve more complex switching configurations. For instance, a double-pole, single-throw (DPST) switch can control two circuits simultaneously, which is not necessary for the operation of the Robertshaw EA thermostat. Similarly, a single-pole, double-throw (SPDT) switch can route the circuit to two different outputs, which also goes beyond the basic requirements of this thermostat model. The presence of multiple contacts in a device is not applicable here, as the Robertshaw EA thermostat's design focuses on a straightforward control mechanism tailored for basic system operations.