The controller allows for the independent control of two frost protection circuits. This means that a single controller can be used to control pavement heating and, at the same time, roof gutters/downpipes, or to manage frost protection on the north and south sides of the roof. The controller also allows for two-stage power control or the control of hot-water frost protection systems.
Both circuits must have their own humidity sensor (ETOR-55 for roof applications and ETOG-55 for ground applications); for roof guttering protection, the ETF-744/99 temperature sensor must also be connected (which is shared between both zones); for ground applications, the temperature is measured by the ETOG-55 humidity-temperature sensor, or, as with roof protection, the shared ETF-744/99 temperature sensor may be used. The temperature sensor is positioned at the ‘coolest’ point of the application (the north side of the building or a shaded area). The sensors are not included with the controller; they must be ordered according to the type of application (road and/or roof protection) and the number of protected zones. The ETO2-4550 controller is mounted in a control cabinet on a DIN rail (9 modules).
