Siemens RVD110, Основная документация

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Siemens Building Technologies Basic Documentation RVD110, RVD130 CE1P2381E
HVAC Products 19 Function block Locking functions 27.05.2004
19 Function block Locking functions
19.1 Operating lines
Line Function, parameter Unit Factory
setting
Range
151 Max. limitation of primary return temperature, constant value °C --- --- / 0...140
152 Max. limitation of primary return temperature, slope 7 0...40
153 Max. limitation of primary return temperature slope, start of
shifting limitation °C 10 –50...+50
154 Max. setpoint of return temperature with d.h.w. heating °C --- --- / 0...140
155 Integral action time, primary return temperature limitations Min 15 0...60
156 Max. limitation of temperature differential °C --.- --.- / 0,5...50
157 Max. setpoint of the return temperature during d.h.w. heating
at the legionella setpoint °C --- --- / 0…140
161 Raising the reduced room temperature setpoint 0 0...10
162 Daily forced d.h.w. heating at the start of release period 1 1 0 / 1
163 Idle heat function Min --- --- / 3...255
191 Locking on the hardware side 0 0 / 1
Settings --- and --.- mean: function is inactive
19.2 Mode of operation
This function block contains all district heat parameters. Since many district heating
utilities demand that the relevant settings be locked, the district heat parameters are
arranged on the ”Locking functions” level. This level can only be accessed with a code.
In addition, it is possible to make a locking on the hardware side. For details, refer to
subsection 22.1.6 “Setting levels and access rights”.
19.3 Maximum limitation of the primary return
temperature
19.3.1 General
The primary return temperature can be limited to a maximum value in order to
•
prevent too hot water from being fed back to the district heating utility
•
minimize the pumping power of the utility
•
comply with the regulations of the district heating utility
Maximum limitation of the return temperature measures the return temperature on the
primary side with sensor B7 and throttles 2-port valve Y1 when the limit value is ex-
ceeded. This maximum limitation is influenced by both the heating circuit and the d.h.w.
circuit. Both consumers have their own limit value.
With plant types no. 2, 3, 7 and 8, the valid limit value is controlled by the heat demand
of the 2 consumers. If both the heating and the d.h.w. circuit call for heat, the higher of
the limit values is used.
Maximum limitation of the primary return temperature has priority over minimum limita-
tion of the heating circuit’s flow temperature.
When the primary valve is fully closed, maximum limitation of the return temperature
will periodically be reset, because in that case, return temperature sensor B7 is located
in standing water. To ensure reliable measurements, the valve will be opened for 1
minute at 20-minute intervals. If, after that, the primary return temperature is still too
high, maximum limitation will become active again, closing the valve again.
For primary temperatures exceeding 130 °C, a Pt 500 temperature sensor can be used.