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Siemens Building Technologies
Basic Documentation RVD110, RVD130
CE1P2381E
HVAC Products
16 Function block D.h.w. actuator 1
27.05.2004
16
Function block D.h.w. actuator 1
16.1 Operating lines
Line
Function, parameter
Unit
Factory setting
Range
111 Actuator Y5 opening time, d.h.w. mixing valve
s
35
10...873
112 Actuator Y5 closing time, d.h.w. mixing valve
s
35
10...873
113 P-band d.h.w. control
K
35
1...100
114 Integral action time d.h.w. control
s
35
10...873
115 Derivative action time d.h.w. control
S
16
0...240
116 Setpoint boost with d.h.w. heating
K
16
0...50
117 Max. d.h.w. temperature setpoint
°C
65
20...95
16.2 Mode of operation
This function block ensures control of the heat exchanger that supplies heat for d.h.w.
heating. It controls valve Y5 in the d.h.w. primary circuit. For details on plant-specific
control, refer to section 17.4 ”Instantaneous d.h.w. heating”.
16.3 Control
process
If the actual flow temperature deviates from the setpoint, the 2-port valve in the primary
return offsets the deviation in a stepwise fashion.
The actuator’s running time, P-band and integral action time must be entered on operat-
ing lines 111 through 114, depending on the type of plant. Different times can be entered
for opening and closing, to allow for actuators with asymmetric running times.
16.4 Setpoint
boost
On operating line 116, the setpoint boost with d.h.w. heating can be entered. Depend-
ing on the type of plant, its action is as follows:
•
With plant types no. 2, 3 and 8: To be entered is the boost of the common flow tem-
perature (acquired with sensor B1) against the d.h.w. temperature setpoint
•
With plant types no. 5: The boost applies to mixing valve Y7
•
With plant type no. 7: The boost applies to both the mixing valve Y5 and the heat
exchanger
•
With plant types no. 4 and 6: No setpoint boost required
The setpoint boost ensures that the heat consumer will receive the flow temperature
level required for the control.
16.5 Maximum
setpoint
On operating line 117, the possible maximum d.h.w. setpoint is to be entered. The set-
ting range is the following, depending on the type of plant:
Plant type Minimum setting value Maximum
setting
value
2, 3, 8
Reduced setpoint (setting
on operating line 42)
Minimum selection of:
•
Setting value on operating line 117
•
Sum of setting values on operating lines
154 and 116
4, 5, 6, 7
Reduced setpoint (setting
on operating line 42)
Setting value on operating line 117
In any case, maximum limitation of the setting range is 95 °C.
