T2 VIA-DU-20 Mode D'emploi page 17

9. Circuit diagram
9.1. VIA-DU-20 with contactor
L1
L2
L3
N
PE
*
30 mA
**
heating of
open space
When using ViaGard MI a 300 mA FI-safety
switch should be used.
* Local values, standards and rules require two- or
four-pole switching using a electrical protection
** Depending on the application, both one- and three-
pole circuit breakers of contactors are possible.
*** Optional and can be activated in a BMS.
9.2. Alarm output
Connection of an
alarm lamp
(diagram) or horn
(rest position)
alarm lamp
L
N
PE
VIA-DU-20
Contactor
***
Air temperature sensor will be needed only
if in menu freezing rain precaution the
parameter "local detection" has been
selected. When weather forecast has been
selected you have to connect the voltfree
contacts of additional device to these
terminals.
Connection of
a current loop
(rest position)
current loop
DC
AC
Floor temp.
and
moisture
***
sensor
Air
temperature
sensor
Notice:
The alarm relay is always active
(switched on) as long as there is no
fault. The alarm relay is potentialfree
but not suitable for the switching of
safety low voltage (SELV) as there is
no double insulation in the device.
17