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Siemens
Basic Documentation RVP360
CE1P2546en
Building Technologies
14 Function block: D.h.w.
2017-07-24
14.9 Boost of d.h.w. charging temperature
Operating line 127 can be used to set the boost of the d.h.w. charging temperature
in Kelvin. The boost refers to the d.h.w. temperature setpoint.
The lower the boost setting, the longer d.h.w. charging takes.
T
Lw
[°C] = T
BWw
+ T
BW
Example:
D.h.w. temperature setpoint (T
BWw
, operating line 26)
= 50 °C
Boost of charging temperature (T
BW
, operating line 127) = 10 °K
Resulting charging temperature setpoint T
Lw
= 60 °C
If a thermostat is used, the boost of the d.h.w. charging temperature must never-
theless be set.
14.10 Maximum d.h.w. charging time
Operating line 129 can be used to set the maximum charging time for d.h.w. stor-
age tanks. The function is always active, independent of the kind of d.h.w. priority
(absolute, shifting, or parallel).
When d.h.w. charging is started, a counter records the charging time. If charging is
ended before the set maximum charging time has elapsed, the counter is reset to
zero. A new charging cycle can be started any time.
But if charging takes longer than the set maximum time, it is aborted and then
locked for the same period of time. Then, charging is resumed, either until the
setpoint is reached or until maximum limitation aborts again the charging time.
The function can be deactivated; in that case, the charging time is not limited.
B
WL
t
2
52
4D
03
ON
OFF
t
T
BWw
T
BW
T
BWw
- SD
BW
t
Lmax
t
Lmax
Charging locked
t
Lmax
Maximum charging time
B
WL
D.h.w. charging
T
BW
D.h.w. temperature
ON
D.h.w. charging ON
T
BWw
D.h.w. temperature setpoint
OFF D.h.w charging OFF
SD
BW
Switching differential d.h.w.
t
Time