RAM 712 KNX
room thermostat for surface-mounted and flush-mounted installation
theben
Version: Dec-10 (subject to change) Page 63 of 65
7.2.2 Positive hysteresis
Heating lasts until the temperature reaches "setpoint value + hysteresis" threshold has been
achieved.
The heating is only switched on again when the temperature falls below the setpoint value.
Heating example:
Heating with setpoint value 20°C, hysteresis = 1 °C and ambient temperature 19 °C.
The heating is switched on and only switches off again when a temperature of 21 °C
(20 °C + 1 °C) is achieved.
It switches on again when the temperature falls below 20 °C.
7.3 Dead zone
The dead zone is a buffer area between heating and cooling operation.
Neither heating nor cooling takes place within this dead zone.
Without this buffer zone, the system would switch continuously between heating and cooling. As
soon as the setpoint value has been under-run, the heating is activated and the setpoint value
would not be achieved. If cooling were then to be started immediately, the temperature would fall
below the setpoint value and switch on the heating again..
Depending on the type of control, the dead zone can be extended by the value of the
7.3.1 Case 1: Heating and cooling with continuous control
Cooling setpoint value
24 °C
DEAD ZONE 4 K
Heating setpoint value
20 °C
The dead zone (4 K) is not affected
