VLR 70 CU - InstaLLatIon
Installation
6
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3. Installation
3.1 Electrical connection
WARNING Electrocution
Only qualified electricians may carry out the connec-
tion in accordance with these instructions. Carry out all
electrical connection and installation work in accordance
with national and regional regulations.
WARNING Electrocution
The connection to the power supply must be in the form
of a permanent connection. Ensure the appliance can be
separated from the power supply by an isolator that dis-
connects all poles with at least 3 mm contact separation.
This requirement can be met by using contactors, circuit
breakers, fuses/MCBs, etc.
WARNING Electrocution
Before working on the electrical installation, disconnect
the circuit from the power supply. Switch off the fuse/
MCB in the fuse box.
Material losses
The specified voltage must match the mains voltage. Ob-
serve the type plate.
Cable length : ≤ 25 m
f
Push the cable routed to the control panel into the flush box.
The cable must protrude 200 mm into the flush box.
f
Push the cable routed to the ventilation unit into the flush
box. The cable must protrude 200 mm into the flush box.
3.1.1 Control unit and power supply unit
Material losses
Interchanging the connections may result in control unit
malfunctions.
Note
When using a differential pressure switch, always in-
terrupt the power supply to the control unit or power
supply unit.
3.1.2 Wiring diagram with more than 2 appliances
1
2
3
4
1
2
3
4
1
2
3
4
1
2
3
4
D
00000
79
67
7
R1
DC +24 V
R2
DC -24 V
R3
Fan +24 V
R4
Fan -24 V
R5
Alarm
R6
Fan 1
R7
Fan 2
f
Assign the appliances to the "Fan 1" and "Fan 2" terminals. Of
the pair of appliances working in differential mode, one must
be connected to the "Fan 1" terminal and the other must be
connected to the "Fan 2" terminal. Check whether the pairs
of appliances are working in differential mode. In differential
mode, one appliance transports the extract air out of the
building to the outside. The other appliance draws outdoor
air into the building.
Odd number of appliances
If there is an odd number, divide the appliances into two groups.
Connect the smaller group to the "Fan 1" terminal.
number of fans
3
5
7
Number of appliances at "Fan 1" terminal
1
2
3
Number of appliances at “Fan 2” terminal
2
3
4