KT-Elektronik
ZPR-D
System variants
System variant 1: Solar thermal system
The program controls the solar circuit pump depending
on the temperature of the solar collector and the
storage tank temperature. If the temperature in the
solar collector is higher than the buffer temperature,
the solar circuit pump is turned on. The solar pump
remains running for a minimum running time and is
earliest turned on after a minimum idle time.
The buffer is charged until the maximum storage tank
temperature is reached or the start-up criteria is not
met any more.
CF1 Sensor 1
SF1 Sensor 2
Overheating protection
In solar thermal systems it comes to the overheating of the solar fluid if the energy from the
collectors can be led away not enough. In this stagnation case the medium can evaporate. In
this case typically used solar pumps cannot build up enough pressure to lift the liquid
medium up to the highest system point (collector escape). In this working condition the pump
is considerably loaded, no solar energy is won to the use and electric energy is used for the
pump.
In the stagnation case the solar pump CP1 is switched OFF at a collector temperature of
130 °C with a hysteresis by 20 K.
Actual pump
running/idle time
The solar pump CP1 is switched on by presentation of the thermal switch condition described
on top on at least 1 minute. The solar pump remains switched off for at least 3 minutes if the
thermal switch condition is not given any more.
Collector minimum
temperature
At low collector temperatures there sinks the efficiency of the solar thermal system, because
the energy consumption of the solar pump is unfavorably high in proportion to the solar
energy yield. The solar pump CP1 is only switched on if the collector temperature at least 20
°C amounts.
Collector Anti-freeze
The collector pump is turned on if the temperature at the collector sensor drops below 5 °C.
At 6 °C it is turned off again, but only after the minimum running time set elapsed.
This customized function is not available in standard devices.
Status indication using Power-LED
● ON ○ OFF
Display
Device powered-on
2 seconds OFF ● ● ● ● ● ● ● ● ● ● ● ● ● ●
Function without additional information
● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●
Sensor break of Sensor1 (Error)
● ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○
E1
Sensor break of Sensor2 (Error)
● ○ ● ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○
E2
Pump minimum running/idle time
● ● ● ● ● ● ● ● ● ● ● ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○
Collector Minimum temperature falls below
○ ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●
H1
Storage tank maximum temperature exceeded
○ ● ○ ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●
H2
Collector overheating protection temp. exceeded
○ ● ○ ● ○ ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●
H3
Collector frost protection temperature falls below
○ ● ○ ● ○ ● ○ ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●
H4
KA_11986_ZPR-D_EN002
5
