9
Version 1 Oct 2009
Important
If the AD unit has an exhaust air outlet spigot fitted, the exhausted air can be routed
outside of the building if required. It is important to keep any ducting used to do so to
a minimum, in order to reduce back pressure within the system.
Filter blocked/System failure signal
With this option the extraction unit will have been fitted with a pressure transducer to
monitor the condition of the filters and to indicate the extractor is running. In addition
to controlling the LED’s on the front of the unit, this signal is available via the green
and white cores of the control cable that exits the cabinet next to the power cable.
The signal is a “volt free” contact, i.e. a closed circuit will exist between the green and
white wires when the filter condition is good and the unit is running. This will change
to an open circuit on filter blockage or system failure. This feature should only be
used on control voltage circuits. The signal can be connected to the laser or
alternatively to operate a beacon, siren or warning device. Open circuit condition of
this circuit will not directly stop the extractor motor.
Remote stop/start
If this facility is installed it enables the extractor unit to be turned on and off by a
signal from the laser.
The red and black cores of the control cable need to be
connected to a 5
– 24v dc supply, which when applied will start the unit and when
switched off will stop the unit.
However the mains power switch must be in the “on”
position for the signal to be effective. (Unless 0V stop/start option was specified when
ordered, for this connect the Red & Black cores together to start the extractor.)
Fig 6
Remote Stop/ Start Over-Ride
If fitted, remote operation can be overridden by using the override switch, which is
mounted inside the unit (see fig. 7).
Fig 7
