Safety Chain, Control Circuit, Main Power Circuit - Viessmann VITOCAL 300-A Installation And Service Instructions Manual

Connection and wiring diagrams
Overview of the PCBs and connection options
Pos. Sensor / KM BUS
e¢W
Buffer cylinder temperature sen-
sor
e¢E
Outside temperature sensor
e¢R
Cylinder temperature sensor,
top
e¢T
Cylinder temperature sensor,
bottom
e¢Z
Flow temperature sensor, heat-
ing circuit with mixer (M2)
e¢U
System flow temperature sensor
(with sensor well, downstream
of the heating water buffer cylin-
der or external heat source)
eYP
Temperature sensor, external
heat source
eYQ
Secondary flow temperature
sensor
Type AWC-I-M: Internal connec-
tion
Type AW-O-M: Install on site in
the heating water flow
Air inlet temperature sensor
Internal connection
Air outlet temperature sensor
Internal connection
Secondary return temperature
sensor
Internal connection

Safety chain, control circuit, main power circuit

In the following wiring diagrams, only
the contacts that are relevant for the
safety chain, control circuit and main
power circuit are shown.
For PCB overview, see from page 70.
174
(cont.)
Type ID
Pt 500 F4
Ni 500 F0
Pt 500 F6
Pt 500 F7
Ni 500 F12
Pt 500 F13
Pt 500 F20
Pt 500 F8
Pt 500 F2
Pt 500 F3
Pt 500 F9
The terminal markings on the PCBs
(e.g. X1.2) are preceded by the num-
bers 1 to 3 (e.g. 3X1.2). These num-
bers are allocated to the 3 PCBs.
Example:
Terminals
3X1.22
3X2.22
3X1.16
3X2.16
3X1.14
3X2.14
3X1.13
3X2.13
3X1.10
3X2.10
3X1.9
3X2.9
3X1.4
3X2.4
3X1.20
3X2.20
3X1.24
3X2.24
3X1.23
3X2.23
3X1.19
3X2.19