RAM 712 KNX
room thermostat for surface-mounted and flush-mounted installation
theben
Version: Dec-10 (subject to change) Page 62 of 65
7 Glossary
7.1 Continuous and switching control
A switching (2 point) control recognises only 2 statuses, On or Off.
A continuous control works with a control variable between 0% and 100% and can thus exactly
measure out the energy input. This achieves a pleasant and precise degree of control.
7.2 Hysteresis
Hysteresis determines the difference between a controller’s switching on and off temperature. It
can be both positive and negative.
A combination of heating and cooling control influences the range of the
Without hysteresis, the control would switch on and off continuously provided the temperature is
within the setpoint value range.
7.2.1 Negative hysteresis:
Heating:
Heating is provided until the setpoint value has been reached.
Afterwards the heating is only switched on again when the temperature falls below the
"Hysteresis setpoint value" threshold.
Cooling:
Cooling lasts until the " setpoint value - Hysteresis " threshold has been achieved.
Afterwards, it is only switched on again when the temperature rises above the setpoint.
Cooling example:
Cooling with setpoint value 25 °C, hysteresis = 1 °C and ambient temperature 27 °C.
The cooling is switched and only switched off again when a temperature
of 24C (25 °C – 1 °C) is achieved.
It switches on again when the temperature rises above 25 °C.
