Relative and Absolute Setpoints

Using the relative setpoint method

1. Set the Base setpoint temperature

   • This represents your comfort mode (2-byte Current temperature setpoint object).

2. Adjust remaining setpoints

   • Set these as relative offsets from the base reference.

3. Changing relative setpoint values

   • If you change the relative setpoint value, the relative temperature of each mode remains the same unless you adjust them too.

4. Antifreeze mode

   • Defined in absolute values.

   • The bus saves the setpoint temperature value when powered off.

Example:

Parameters:

• Base setpoint temperature: 21 °C

• Reduced heating in standby mode: 5 °C

Calculation:

• 21 °C – 5 °C → Heating in standby heats up to 16 °C

Parameters:

• Base setpoint temperature: 23 °C

• Reduced heating in standby mode: 5 °C

Calculation:

• 23 °C – 5 °C → Heating in standby heats up to 18 °C

Setting dead zone limits

To prevent frequent switching between heating and cooling, you can set upper and lower limits for the dead zone. Se more here: Dead Zone.

Example:

Parameters:

• Upper dead zone: 2 °C

• Lower dead zone: 2 °C

• Base setpoint temperature: 21 °C

Heating:

• Actual temperature ≥ Base setpoint temperature + Upper limit dead zone

• 25 °C ≥ 21 °C + 2 °C → Too warm → Heating switches to cooling

Cooling:

• Actual temperature ≤ Base setpoint temperature – Lower limit dead zone

• 18°C ≤ 21°C – 2°C → Too cold → Cooling switches to heating

Absolute setpoint method

The setpoints for cooling or heating can be defined as absolute values, allowing total control over the desired room temperature. The thermostat regulates the room temperature based on the setpoint defined at any given moment.

To set the temperature, use the 2-byte object Current temperature setpoint. Depending on the set value and the parameterized setpoints for each special mode, the appropriate mode is established.

Minimum zone between heating and cooling setpoints

The parameter Minimum zone between heating and cooling setpoints defines the minimum temperature interval between the setpoints for cooling and heating in comfort mode.

The system automatically switches between heating and cooling based on the comfort mode setpoints:

• Cooling activates automatically when the current temperature exceeds the cooling comfort mode setpoint.

• Heating activates automatically when the current temperature falls below the heating comfort mode setpoint.