Low Fire Hold Via 3-Position Output On A Steam Boiler; Procedure - Steam Boiler With An Rwf55 With 3-Position Output (Lmv37 Only) - Siemens LMV3 series Technical Instructions

LMV Series
Low Fire Hold with an RWF55 (continued)
Procedure – Steam Boiler with an RWF55 with 3-position Output (LMV37 only)
In the case of steam boilers, temperature sensors located in the boiler water jacket are
recommended. Technical Instructions SEN-1000 provides additional information on
temperature sensors.
1. Set the following parameters in the RWF55:
ConF > Inp > Inp1 > SEn1 = signal type of pressure sensor being used
ConF > Inp > Inp1 > SCL1 = 0
ConF > Inp > Inp1 > SCH1 = high end of the range of the pressure sensor
ConF > Inp > Inp3 > SEn3 = type of RTD being used for a belly sensor
ConF > Inp > Inp3 > dF3 = 0
ConF > Cntr > CtYP = 1
ConF > AF > FnCt = 11
ConF > AF > AL = temperature to enable low fire hold
ConF > AF > HYSt = deadband around low fire hold temperature
2. Wire the LMV37 and RWF55 as shown in Figure 5:
Figure 5: Low Fire Hold via 3-position Output on a Steam Boiler
See page 19 for an example of the low fire hold operation.
SCC Inc. Page 11
Technical Instructions
Document No. LV3-1000
Appendix A