Viessmann VITOCAL 151-A Installation And Service Instructions Manual page 50

Installation sequence
Electrical connection
Luster terminals for 230 V~ components and digital inputs
Terminals Component/function
9 to 11 Circulation pump for buffer discharge
P1.N
P1.
P1.L
12 to 14 DHW circulation pump
P2.N
P2.
P2.L
Digital input functions
■ The simultaneous connection of several functions to
1 digital input is not possible.
■ With on site power supply, ensure phase matching
with the control unit voltage input: See chapter "Con-
trol unit power supply".
■ Set the required parameters during commissioning:
See chapter "Commissioning assistant"
The following functions are available via the 4 digital inputs:
Functions
143.2
Power-OFF
—
G
Smart Grid
—
DHW circulation X
pump demand
External demand
—
50
(cont.)
Switching contacts
143.3 143.4 143.5
X
— —
X X
—
— — —
X
— —
C
Explanation
Configurable connection
Output: 230 W
■
Voltage: 230 V~
■
Max. switching current: 1 A
■
Recommended flexible connecting cable:
2
■ 3 x 1.5 mm
Max. cable length: 50 m
■
Output: 230 W
■
Voltage: 230 V~
■
Max. switching current: 1 A
■
Recommended connecting cable:
3 x 1.5 mm 2
■
Max. cable length: 50 m
■
Explanation
Requires floating N/C contact:
Closed: Heat pump operational
■
Open: Heat pump shut down
■
For the instantaneous heating water heater, the
■
stages to be switched off can be selected.
The power supply for the heat pump control unit
■
(3 x 1.5 mm 2 ) and the cable for the power-OFF signal
can be combined in a single 5-core cable.
For further information regarding power-OFF: See
■
chapter "Power supply".
In connection with Smart Grid:
Do not connect the power-OFF signal.
The power-OFF function is integral to Smart Grid. The
power-OFF signal must therefore not be connected.
External demand, DHW circulation pump
External demand from compressor and pumps