Varifan ECS 5M, User Manual

Page: 18 / 52

Page 18
ECS 5M
VARIFAN
RECOMMENDED CONTROL
BACKUP
WARNING AND PRECAUTIONS
Equipment failure, blown fuses and/or tripped breakers
may prove harmful to the content of the building. It is
therefore strongly recommended to install backup devices
and alarm or warning devices (see example fig. 7).
BACKUP THERMOSTAT. If the Varifan control fails, then
the thermostat will start the dedicated fan at full speed
when the temperature will reach the T15-WD set value.
Therefore, the T15-WD should be accessible for its
adjustment and it should be set at the same temperature
as the alarm, i.e. approximately 5ºF above the fan relative
set point.
BACKUP POWER SOURCE. The DPDT relay connects
to the source 1 in normal operation but will switch to the
source 2 if source 1 is off. The relay shall be chosen to
support the load connect to it.
ALARM CIRCUIT. In normal operation, the alarm circuit of
the Varifan Control is a short circuit. But if the Varifan
control is defective or if there is no power applied to it,
then the alarm circuit of the control will be an open circuit.