33
F1
(F2)
A1
A1
A2
ON
Impulso
A3
ON
F4
F3
F5
Fig. 2.21
System 12
Outputs:
A1 Collector pump (speed control) and
storage cylinder pump
A2
Switch to bottom zone
A3
Switch to middle zone
Inputs:
F1
Collector temperature probe
F5
Temperature probe in middle of stor-
age cylinder
F3
Temperature probe at top of storage
cylinder (A1 max temperature moni-
toring)
F4
Temperature probe at bottom of stor-
age cylinder
F2
(optional) Return temperature probe
for heat flow measurement
Impulse (optional) pulse transducer for volu-
metric flow meter
Switching conditions for A1
Heat production (difference between storage
cylinder and min. temp.)
ON: F1 - F4 > P30 and F1 > P40
OFF: F1 - F4 < P31
or F1 < P41
Maximum storage cylinder temperature
OFF: F3 > P50
ON: F3 < P50 - 5°C
Maximum collector temperature
OFF: F1 > P42
ON: F1 < P42 - 10°C
Switching conditions for A2:
ON: A1 = ON and F1 – F5 > P32
and F5 < ( P50 - P32)
OFF: A1 = OFF
or F1 – F5 < P33
or F5 > (P50 - P33)
Switching conditions for A3:
ON: A1 = ON and F1 - F3 > P32
and F3 < ( P50 - P32)
OFF: A1 = OFF
or F1 - F3 < P33
or F3 > (P50 - P33)
impulse