Viessmann Vitocal 300-G Installation And Service Instructions For Contractors page 82

Installation sequence
Electrical connections in the heat pump control...
Terminals Function
X3 ■ Power supply terminals
of the control unit "L1"
and auxiliary compo-
nents
■ Switched phase L1:
X3.1, X3.2, X3.3, X3.7,
X3.11, X3.13
X3.1 Phase switched
X3.2 Signal "External blocking"
X3.14 (external blocking of com-
or at exter- pressor and pumps, mixer
nal exten- in control operation or
sion H1 CLOSED)
Note
The system may no longer
be protected against
frost.
X3.3 Flow limiter, well circuit
X3.4
82
Explanation
Terminals for message and safety connec-
tions
Note
Switched phase can be used for on-site
system components. Observe max. load.
Requires floating N/O contact:
■ Closed: Blocking enabled
■ Open: No blocking
■ Breaking capacity 230 V~, 2 mA
Note
■ These and further external functions,
such as swimming pool water heating,
cascade or external set value default
can alternatively be connected via exter-
nal extension H1.
Installation instructions "External
extension H1"
■ If a swimming pool water heating facility
is connected to external extension H1,
no other external function can be con-
nected to external extension H1.
Floating contact required:
■ Closed: heat pump operational
■ Open: Heat pump shut down
■ Breaking capacity 230 V~, 0.15 A
With a connected flow limiter, no jumpers
should be installed.
(cont.)