O2 control compensates for interference variables which have a negative effect on the fuel-air ratio. The combustion air is subject to temperature, humidity and pressure fluctuations. The fuel is subject to temperature, heat value and pressure fluctuations.

For each operation mode, O₂ correction can be activated separately and an individual O₂ setpoint curve can be entered based on the burner capacity. The O₂ correction influences the load position of the air or fuel channels parameterized via the channel functions.

The O₂ controller receives its setpoint from the specified O₂ setpoint curve based on the current load position. From the setting value of the O₂ controller (-100.0 % to +100.0 %), the current load position, the O₂ correction value at low load and the O₂ correction value at full load the O₂ correction for the load position is calculated.

O₂ correction should act on the air ducts. If the plant uses fans with speed control, then O₂ correction must be used for speed control and for the corresponding damper. O₂ correction may only act on either the air or the fuel channels for each operation mode.

O2 correction value

X

Load position

Y

Channel position

A

Air channel

B

O₂ correction max

C

O₂ correction min

See also

• Channel function