30
FA ROTEX Solaris RPS4 -
04/2016
6
x
FlowSensor
The following instructions help with determining the setting
values and guarantee optimum thermal yield with low power con-
sumption:
Ɣ
Adjust the switch-on temperature difference [Delta T on] so
that the system remains in operation under constant solar
radiation conditions, and does not switch off immediately
when the collector temperature drops due to heat removal.
The lower this value can be adjusted, the longer will be the
operating periods with a correspondingly higher heat yield.
If the adjusted switch-on temperature difference is too low,
the collector will already cool down so far during filling, that
the switch-off temperature difference is reached.
Î
The pumps are switched off immediately, with resulting
lower heat yield and higher power consumption.
Ɣ
Adjust the switch-off temperature difference [Delta T off] so
that the heat yield obtainable at the switch-off point is higher
than the electrical power required to drive the pump.
Î
Since the power consumption of the solar operating pump
P
S
is virtually independent of the size of the connected
solar panel array, but the thermal power that can be
exploited is directly dependent on the number of solar
panels, the parameter value on a few solar panels is set
higher, but with multiple solar panels it is set lower.
Ɣ
The run time [time P2] for maximum output of the solar
operating pump P
S
to be set so that, in all cases, the total
cross-section of the flow line is filled with water. Determine
the time from the detection of air noises from switching on the
solar operating pump P
S
to entry into the storage tank and
add a safety factor of 20 secs. The filling period depends on
the adjusted flow rate, the number of collectors, system
height, and the length of the connecting pipe
Ɣ
The maximum storage temperature [TS max] is set according
to the individual conditions. The higher the value of the
parameter, the higher will be the available heat storage
capacity, and thus the output potential of the ROTEX solar
system.
System switch-on involving steam generation can often be
disconcerting for the operator. In order to reduce boiling noises
and steam emission, the restart temperature [TK permitted] is set
in the factory. The Solaris R4 regulator only switches the solar
operation pump P
S
on again when the collector temperature has
fallen 2 Kelvin below the adjusted parameter value. Conse-
quently, the system runs without evaporation in the collector.
However, on a cloudless day, this can lead to a situation where
the system only switches on again in the late afternoon, although
the storage cylinder temperature permits additional heating.
Ɣ
In order to maximise energy input, set the [TK permitted] to a
value greater than 100°C and thus deactivate the restart
protection function.
In this case the system operator should be advised of audible
bubbling noises and steam knocking during filling.
6.4.2 Additional settings for your solar system
The following setting instructions apply only to basic setting with
fitted FlowGuard:
Ɣ
Activate manual mode.
Ɣ
After filling the system completely, set the water flow rate so
that each solar panel is transited at 90 to 120 l/h. Influence the
flow rate either by setting the speed stage at the solar
operating pump PS or/and by setting the FlowGuard
(regulating valve with flow indication). Reference values for
correct valve and pump stage settings are listed in tab. 6-6.
Ɣ
Switch the Solaris R4 regulator after completing the setting.
Tab. 6-6 Setting the flow rate on the FlowGuard (FLG)
During commissioning, the system parameters must be
adjusted individually to suit the installed system, and
might need fine tuning during subsequent operation.
Usually, the system will operate with the default set-
tings.
WARNING!
Temperatures in excess of 60°C can arise in the
solar storage tank.
Ɣ
Install scalding protection.
– Scalding protection VTA32 (
15 60 15
)
– Screw connection set 1" (
15 60 16
)
Number of
solar panels
Nominal flow
in l/min
Desired flow in l/hour
2
3.0 to 4.0
180 to 240
3
4.5 to 6.0
270 to 360
4
6.0 to 8.0
360 to 480
5
7.5 to 10.0
450 to 600
For rapid and safe filling of the system, always set the
solar operating pump P
S
to a high speed stage, if the
installation height H, as a height difference between the
installation surface of the solar storage tank and the top
of the solar panel does not exceed 10 m and an adequate flow
rate still sets itself.
Even if the flow volume is set correctly, the cut-in tem-
perature difference [Delta T on] and good weather con-
ditions will occasionally shut down the solar system.
With a rising or setting sun, and an increasing storage
cylinder temperature, the collector temperature gradually falls
after the pumps have been switched on, i.e. the switch-off con-
ditions are met. The continuing solar radiation will increase the
temperature of the solar panels, the pumps will operate and the
system will cycle because the solar radiation is no longer suffi-
cient for continuous operation. The FlowSensor reduces this
effect by pump speed regulation.
