Description

Purge suppression is used to prevent purging of the furnace, the flue gas ducts and the FGR channel. You can parameterize various types of purge suppression:

Properties

Type

Selection parameter

[0] (No) Never suppress

If all parameters of the "Purge" parameter group are parameterized as FALSE, then the furnace is purged without additional restrictions before burner start.

[1] (Yes) Always suppress

Purging of the furnace, the flue gas channels and the FGR channel is prevented. (e.g. waste incineration plants).

[2] (Yes) by digital input

This type of purge suppression is used for plants with at least two burners on one furnace (e.g. for double flame tube boilers).

You can use the digital input "purge suppression" to suppress running to the purge position and the purge time on the FSC.

FSC configuration for digital inputs must include the "suppress purge process" input signal.

If the purge suppression input opens after the purge sequence has started (safety interlock circuit after fan start-up is closed) and before the ignition flame safety time has elapsed, then a safety shut-off is triggered with the message (204) "FSC: Prohibited purge suppression".

[3] (Yes) automatically (DIN EN 676)

Purge suppression is performed automatically after a controlled shutdown. Special shut-off equipment is required for this purpose (in Germany in compliance with DIN EN 676).

The complete purge sequence is performed after the supply voltage has been restored, after a safety shut-off or after 24 hours (even if the burner was successfully switched off via a controlled shutdown).

[4] (Yes) automatically, air dampers open (DIN EN 676)

Purge suppression is performed automatically after a controlled shutdown. The channels with the channel function 1, 2, 4, 6, 7, 11 and 12 are run to their purge positions.

Special shut-off equipment is required for this purpose (in Germany in compliance with DIN EN 676).

The complete purge sequence is performed after the supply voltage has been restored, after a safety shut-off or after 24 hours (even if the burner was successfully switched off via a controlled shutdown).

[5] (Yes) automatically, only gas operation (DIN EN 676)

Purge suppression is only performed automatically in combination with gas firing operation mode after a controlled shutdown. Purging must always be performed in oil firing operation mode.

Special shut-off equipment is required for this purpose (in Germany in compliance with DIN EN 676).

The complete purge sequence is performed in the following cases even if a controlled shutdown of the burner was performed successfully:

• when oil firing operation mode is preselected

• after the supply voltage has been restored

• after a safety shut-off

• after 24 hours

Reference

1027, 1028, 1029, 1030, 1031

DOC-727884582