Lamtec BT300 BurnerTronic, Руководство пользователя

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4 Design and Functions
Correction of Ratio Curve "Air" for Inactive Flue Gas Recirculation
Reason for This Function
When a burner is operated with flue gas recirculation, it might be necessary for the combustion
air damper to be opened wider during operation with flue gas recirculation than in operation with-
out flue gas recirculation. If burner is activated without flue gas recirculation, this may cause con-
siderable air excess. Using the function "correction of ratio curve - air", the combustion air
damper position for inactive flue gas recirculation can be reduced (closed) by up to 20,0%.
Description of Function
The correction channel is determined by the parameters 704 (for curve set 1) and 705 (for curve
set 2). Using parameters 706-715, the reduction of the air damper position at every programmed
point of the curve of curve set 1 can be adjusted. Using parameters 716-725, the reduction of the
air damper position at every programmed point of the curve of cufve set 2 can be adjusted.
Fig. 4-33 Correction of the ratio curve air with inactive flue gas recirculation
4.8 Continuous Purge
Requirement for continuous ventilation: P330 = 1
BT300 activates also the fan output in BURNER OFF mode and moves all control dampers
up to version 3.8.0.0 completely open.
From version 3.9.0.0, the pre-purge limits in parameters 365 - 369 are observed.
The "Burner ON" signal switches off the fan to check the air pressure switch.
As soon as the air pressure switch has switched off, the fan is switched on again and the burn-
er starts with the normal start-up sequence.
If the air pressure switch does not switch off after 25 s, BT300 changes to fault position and
indicates fault U929. Some internal faults of the BT300 also switch off the output for the fan.
NOTICE
The BT300 switches off the fan in the fault condition.