Operating instructions

27
Heating system designs
System version 7 (cont.)
Possible applications
If the distributor is located in remote
sub−stations (> 20 m). The heat
transfer to the heating circuits must
be able to be reduced. In multi−boiler
system without Vitotronic 333,
cascade and cylinder control must be
provided by a higher control unit.
The distribution pump will be
regulated by the higher control unit.
It must be started when a boiler is
enabled.
Temperature sensor T1 reduces or
closes the mixer if the required
minimum return temperature is not
achieved. Size the distribution pump
to 110% of the total heating system
flow rate.
The boiler is best protected when
regulating the heating circuits via
Vitotronic050 connected to the
boiler control unit.
No additional on−site protective
measures are required.
Temperature sensor T1
Wiring for reducing the volume flow
in heating systems with heating
circuit control units, which are not
connected to the boiler control unit
via the LON BUS.
Required coding: "0d:1" and
"4C:2".
sÖA1 Mixers closed
A Contactor relay,
part no. 7814681
B Downstream heating circuit
controller, contact closed:
Signal for "Mixer closed".
C Mains electrical connection
230V~/50Hz
D Junction box, on site
5862730GB
A
A
D
A
C
L1
N
PE
closed closed closed
12n...
K1 K2
B
20 20
A1 A1