Viessmann VITOCAL 350-A Installation And Service Instructions Manual page 59

Electrical connections: Heat pump control unit
Terminals Function
X3.2 "External blocking" signal (external blocking
X3.14 of compressor and pumps, mixer in control
or at external mode or CLOSE)
H1 extension
Note
The system may no longer be protected
against frost.
X3.6 Power-OFF
X3.7
G
X3.8 Contact humidistat
X3.9 or
Jumper
(cont.)
Explanation
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 heating, cascade or external set
value default can alternatively be connected via
external H1 extension.
"External H1 extension" installation in-
structions
If a swimming pool heating facility is connected
■
to external H1 extension, no other external
function can be connected to external H1 exten-
sion.
Requires floating N/C contact:
Closed: No blocking (safety chain continuous)
■
Open: Blocking enabled
■
Breaking capacity 230 V~, 0.15 A
■
No jumper should be installed if a power-OFF
contact is connected.
Note
No parameters need to be set.
■
As soon as the contact opens, the compressor
■
is "forced" OFF.
The power-OFF contact signal causes the sup-
■
ply voltage to the relevant components to be
switched off (subject to power supply utility).
For the instantaneous heating water heater, the
■
stages to be switched off can be selected (pa-
rameter "Output for instant. heating water
heater at power-OFF").
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".
Requires floating contact:
Closed: Safety chain has continuity.
■
Open: Safety chain interrupted; heat pump shut
■
down.
Breaking capacity 230 V~, 0.15 A
■
Connect on site:
Connected in series, if both safety components
■
are installed.
Insert jumper if no safety components are
■
installed.
Installation sequence
59