Viessmann PLC VITOCAL 350-HT PRO Service Instructions For Contractors page 56

PCBs and connection options
Expansion PCB
(cont.)
Connection
Analogue in X25
Analogue in X26
Analogue in X27
Digital in X28
Digital in X29
56
Terminal Address
1 AI 2
3 AI 3
5 AI 4
7 AI 5
1 AI 6
3 AI 7
5 AI 8
7 AI 9
1 AI 10
3 AI 11
5 AI 12
7 AI 13
1 I 288
3 I 289
5 I 290
7 I 291
9 I 292
1 I 293
3 I 294
5 I 295
7 I 296
9 I 297
Explanation
0-10 V specified set value for high tempera-
ture maintenance
0 V = 40 °C
■
10 V = 90 °C
■
Room temperature sensor
Heating water buffer cylinder temperature
sensor, top
Heating water buffer cylinder temperature
sensor, bottom
Outside temperature sensor
Temperature sensor, residual heat flow
Temperature sensor, cooling flow
Coolant buffer cylinder temperature sensor,
top
Coolant buffer cylinder temperature sensor,
bottom
Flow temperature sensor, cylinder loading
system (DHW)
Cylinder temperature sensor (DHW)
Flow switch, heat source
PSU enable
Enable, heating of heating water buffer cylin-
der
Enable, cooling of coolant buffer cylinder
Enable, DHW heating
Pressure switch, heat recovery
Pressure switch, residual heat
Flow switch, AC/NC cooling