Siemens RVL481 - Page 6

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Siemens Heating and D.h.w. Controller RVL481 CE1P2541en
Building Technologies Contents 20.05.2008
11.2.2 Setpoint rise...................................................................................................48
11.3 3-position control............................................................................................48
11.4 Excess mixing valve or heat exchanger temperature ....................................49
11.5 Pulse lock.......................................................................................................49
12 Function block "Boiler"...............................................................................50
12.1 Operating lines...............................................................................................50
12.2 Operating mode .............................................................................................50
12.3 Limitations......................................................................................................50
12.3.1 Maximum limitation of the boiler temperature................................................50
12.3.2 Minimum limitation of the boiler temperature.................................................51
12.3.3 Actions during d.h.w. heating.........................................................................51
12.4 2-position control............................................................................................51
12.4.1 Control with a single-stage burner.................................................................51
12.4.2 Control with a 2-stage burner.........................................................................52
12.4.3 Frost protection for the boiler.........................................................................53
12.4.4 Protective boiler startup .................................................................................54
12.4.5 Protection against boiler overtemperatures ...................................................55
12.5 Operating mode of pump M1 .........................................................................55
13 Function block "Setpoint of return temperature limitation"....................56
13.1 Operating line.................................................................................................56
13.2 Description.....................................................................................................56
13.3 Minimum limitation of the return temperature ................................................56
13.3.1 Acquisition of measured values .....................................................................56
13.3.2 Mode of operation..........................................................................................56
13.3.3 Mode of operation with a single device (with no bus) ....................................57
13.3.4 Mode of operation in interconnected plants...................................................57
14 Function block "District heat" ....................................................................58
14.1 Operating lines...............................................................................................58
14.2 Limitations......................................................................................................58
14.2.1 Maximum limitation of the primary return temperature ..................................58
14.2.2 Maximum limitation of return temperature differential (DRT limitation)..........59
14.2.3 Integral action time.........................................................................................60
14.2.4 Minimum stroke limitation (suppression of hydraulic creep) ..........................60
14.2.5 Flow limitation ................................................................................................60
15 Function block "Maximum limitation of the return temperature, d.h.w."61
15.1 Operating line.................................................................................................61
15.2 Purpose..........................................................................................................61
15.3 Function .........................................................................................................61
16 Function block "Basic settings d.h.w." .....................................................62