© RESOL 10263 flo
wcon_sensor
.monen.ind
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F lo w C o n S e n s o r / S e n s o r H E
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If a sufficiently high
D
T is identified during an identification
phase, a stabilising phase follows. The pump remains active at
minimum speed until the system volume has been circulated
completely. If the
D
T is still sufficiently high at the end of the
circulation, the controller starts the solar loading. If the
D
T
measured is not sufficiently high, a pause is run.
In the system display and the status menu, the remaining
time of the phase is displayed as a countdown (mm:ss).
The duration of the stabilising phase adjusts itself to the
current flow rate. This may lead to sudden changes in the
countdown displayed if the flow rate fluctuates.
Stabilising
If the
D
T measured at the end of the stabilising phase is
sufficiently high, solar loading starts. Solar loading will be
active as long as there is a sufficiently high
D
T and none of
the switch-off conditions have been fulfilled. During solar
loading, the pump speed is controlled according to the
adjusted speed control mode.
Loading
If this function is activated, the system is not shut down upon
reaching Tstmax. Instead, the system will be run in a way that
ensures a maximum stand-by time for operational readiness.
If, during solar loading, the return temperature exceeds the
adjusted value Tstmax by at least 5 K, the controller starts
the
readiness
, until Tstsec is reached or the return tempe-
rature falls below Tstmax.
During
readiness
, the pump speed is controlled with Tstsec
as target flow temperature.
Readiness
If the
D
T falls below the minimum value of 5 K during solar
loading, an overrun phase is started immediately. The pump
remains active at minimum speed, until the system volume
has been completely circulated. If the
D
T rises above the
minimum value again, the overrun stops right away and the
solar loading is continued. If the
D
T remains insufficiently high
until the end of the circulation, a pause is run.
In the system display and the status menu, the remaining
time of the phase is displayed as a countdown (mm:ss).
The duration of the overrun phase adjusts itself to the
current flow rate. This may lead to sudden changes in the
countdown displayed if the flow rate fluctuates.
Overrun
Whenever an error occurs (for more information about
the different error conditions see chap. 16), an inhibition
is triggered. When the error has been eliminated, the in-
hibition ends and a pause follows (save for “Leakage” and
“Overpressure”, see chap. 16.2). Outside the testing time
frame, the controller goes straight into standby phase when
an inhibition has ended.
Inhibition
If this function is activated, the store is cooled via the collector
field, if it has been loaded to a temperature higher than Tstmax
by the
readiness function
.
If the return temperature exceeds Tstmax and the
D
T sinks
to a negative value, store cooling commences. The pump is
run at 100 % speed until the
D
T is once again positive or
the return temperature has fallen below Tstmax.
Store cooling
Whenever a pause or an inhibition starts, the current pressu-
re value is stored. If the pressure rises by more than 0.2 bar
during the pause or inhibition, an evaporation of heat transfer
medium is assumed.
The controller inhibits the system operation until the pres-
sure has sufficiently decreased. After that, a five minute
pause is run.
Stagnation
Note:
Evacuated tube collectors have a very low heat
loss. An effective store cooling via the collector
field is not possible. The store cooling function
should not be activated if there are evacuated
tube collectors in the system!
Note:
Solar loading is not aborted by the end of the
calculated testing time frame. If the
D
T remains
sufficiently large, solar loading may last well be-
yond the end of the testing time frame.