Viessmann VITOCAL 300-G Installation And Service Instructions For Contractors page 30

Installation sequence
Electrical connection
Plug
sXS
Clamps Function
222.1 Control of mixer motor for external
heat generator
Mixer CLOSE signal
222.2 Control of mixer motor for external
heat generator
Mixer OPEN signal
222.3 Control of external heat generator
222.4 and high limit safety cut-out (on site,
max. 70 °C), to simultaneously switch
off the following components:
Secondary pump
■
External heat generator
■
30
(cont.)
Explanation
Connection values:
Output: 10 W
■
Voltage: 230 V~
■
Max. switching current: 0.2(0.1) A
■
Connection values:
Output: 10 W
■
Voltage: 230 V~
■
Max. switching current: 0.2(0.1) A
■
Floating contact
Note
The switching contact is a floating N/O contact that is
■
closed when a heat demand is issued.
Never route extra low voltage (ELV) via this contact.
■
For that, a relay must be fitted on site.
The boiler water temperature sensor in the external
■
heat generator (plug F20) must capture the average
temperature of the external heat generator.
Connection values (contact load):
Voltage: 230 V~
■
Max. switching current: 4(2) A
■
Connect the high limit safety cut-out:
See the following chapter.