AES VDMA 24177

2
Electrical installation
In the case of electrically operated systems, the cables must be monitored for short-circuit,
earth connection and open circuit if the operated condition is not achieved by switching off
the power supply. An acoustic or visual signal on the control panel must indicate when there
is an error.
The switching equipment for the smoke extraction fan must be located outside the smoke
extraction area and must be accessible from escape and rescue routes.
Circuit, control, regulation
The smoke extraction case takes priority over all other functions of the smoke extraction
fans.
This means that, by means of a suitable switching device
> the fan (motor) is to be switched on
> all the thermal and electrical monitoring elements are to be bridged or switched off
> the fan is to be switched to the rated (usually the maximum) speed
> speed control devices must be circumvented.
It must be ensured that the fan remains switched on after the automatic switch-on and
cannot be switched off accidentally or deliberately.
This is achieved in that there are no external, freely accessible OFF switches on the
switchgear and that this function is accessible only to authorised operating personnel.
Control of fans in case of fire is neither useful nor permissible - the only function of the fan is
to operate for the defined time at the rated speed and delivery rate.
Monitoring, activation
The protection of persons in case of fire can be achieved only by keeping escape and rescue
routes promptly and sufficiently free of smoke until the fire brigade arrives.
Particular importance is attached here to the immediate activation of the mechanical smoke
extraction systems.
Therefore, smoke extraction fans must have automatic activation devices that respond to
smoke (smoke detectors or smoke switches).
They can also be activated by a fire alarm system if this includes smoke detectors.
It is possible to deviate from this if smoke extraction flaps with their own sensor and
activation units are part of the smoke extraction system; the smoke extraction fans must then
be connected into the wiring system for the smoke extraction flap and the associated
activation device. In addition it must be possible to put smoke extraction fans into operation
via switch devices with manual pushbuttons.
Only activation devices with general building authority approval for the purpose of use may
be used for the activation of smoke extraction fans.
Power supply
The distribution must be regulated in such a way that the power supply is retained even if the
rest of the supply inside the building has been cut off in an emergency (separate isolating
switch).
Controllers by HÖTE-ELECTRONIC-GMBH meet all prescribed requirements
and functions and are generally accepted by the TÜV!