Siemens RVL471 - 22 Function Block Multi-Functional Relay; Operating Lines; Functions; No Function

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Siemens Building Technologies Basic Documentation RVL471 CE1P2524E
HVAC Products 22 Function block "Multi-functional relay" 23.10.2002
22 Function block "Multi-functional re-
lay"
The RVL471 features a multifunctional relay whose function is selected on this block.
This relay is also used for controlling an electric immersion heater for d.h.w. heating.
This means that if the parameters of the controller are set to "Electric heater for d.h.w.
only" (plant type x–5) or changeover operation, the relay cannot used for any other
functions. The settings on that block are then inactive.
22.1 Operating lines
Line Function, parameter Unit Factory
setting
Range
141 Function of multifunctional relay 0 0...7
142 Manually ON / OFF 0 0 / 1
143 Outside temperature switch, switch-off value for occupancy time °C 5.0 −35...+35
144 Outside temperature switch, switch-off value for non-occupancy
time
°C –5.0 −35...+35
145 Outside temperature switch, switching differential °C 3 1...20
146 Selection time switch 3 1...3
22.2 Functions
The following eight functions can be assigned to the multi-functional relay:
Operating line 141 Function
0 No function
1 Outside temperature switch
2 ON / OFF according to the time switch
3 Relay energized in the event of fault
4 Relay energized during occupancy time according to the heating
program (with no optimization)
5 Relay energized during occupancy time according to the heating
program (including optimizations)
6 Relay energized, if there is demand for heat
7 Manually ON / OFF
22.2.1 No function
No function is assigned to the multifunctional relay.
22.2.2 Outside temperature switch
Using the outside temperature switch, any pieces of equipment can be controlled de-
pending upon the outside temperature. This function requires an outside sensor or an
outside temperature signal that is delivered via the data bus.
2 different switch-off values can be set for both the occupancy and non-occupancy time
(operating lines 143 and 144). The switch-on point lies below the switch-off point, the
difference being the set switching differential (operating line 145). Depending on the set-
ting made on operating line 146, the occupancy and nonoccupancy times may be those
of
• the heating program (setting “0”)
• switching program 2 (setting “1”)
• switching program 3 (setting “2”)