Siemens LMV50 series, Руководство пользователя

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Building Technologies Basic Documentation LMV5... CC1P7550en
19 O2 trim control with LMV52 and PLL52 22.05.2018
19.4.2 Load limitation with O2 trim control
O2 trim control becomes inactive below the low-fire adaption point LowfireAdaptPtNo .
Parameter Gas: LowfireAdaptPtNo
Oil: LowfireAdaptPtNo
If O2 trim control and O2 alarm are to be inactive below a higher output, the O2
CtrlThreshold parameter is also available.
Parameter Gas: O2 CtrlThreshold
Oil: O2 CtrlThreshold
Attention!
If the load falls below one of the two thresholds named above, O
2
control and O2
alarm become inactive and the system operates along the parameterized ratio
control curves.
If the load increases and exceeds one of the two thresholds named above by 5%
(absolute value), the O
2
trim controller is reinitialized and activated together
with the alarm.
19.4.3 Startup
When setting parameter OptgMode to O2 Alarm or O2 Control , startup is prevented
until the sensor reaches its operating temperature.
When setting the parameter to
conAutoDeac, the burner is started immediately and O
2
trim control is activated only when the sensor reaches its operating temperature and
the O2 sensor test has been successfully completed.
Also refer to the chapter Heating up the QGO20 sensor after power On.
19.4.4 Heating up the QGO20 sensor after power ON
When the system or the PLL52 is switched on for the first time, the cold QGO20 is
slowly heated up until its operating temperature is reached.
When temperature of 700
°C is reached, the sensor needs another 10 minutes t to be complete heated through.
This waiting time does not apply following interruptions to the power supply if the
temperature on startup is >690 °C.
A longer time applies when the plant is commissioned (refer to QGO20 Basic
Documentation P7842).
When setting parameter
OptgMode to O2 Alarm or O2 Control, startup is prevented
until the sensor reaches its operating temperature, followed by burner startup. O2 trim
control in the operating position is activated the moment the controller locking time has
elapsed.
When the parameter is set to
conAutoDeac, the burner is started immediately. O
2
trim
control in the operating position is performed only when the sensor reaches its
operating temperature and the O2 sensor test has been successfully completed.