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Operation and Maintenance Manual
– SCD Smoke Dampers
Version 1
Date 04 2018
Page 35 of 81
5. DRIVES AND CONTROL
In SCD smoke dampers, a basic function of emergency opening in order to extract
smoke is carried out by a pneumatic or electric 24 V actuator.
The power transmission from the actuator to the damper cover is carried out by a
special mechanism, and the cover position is set by a MHV spring lock.
Rys. 12. MHV spring lock.
In the case of control system failure, which prevents the SCD damper leaf from
closing, please contact Smay Sp. z o.o. Service Department.
For the leaf emergency closing, when the control system does not operate, before the
service staff arrives, it is necessary to disconnect the immobilised actuator from the leaf (by
disconnecting the eye bolt from the MHV lock or by unscrewing the eye bolt from the
actuator, or by disconnecting the E actuator from the fixing console), close the leaf and
protect it against opening.
5.1.
PNEUMATIC DRIVES
5.1.1. CONFIGURATIONS
For emergency opening, dampers with a pneumatic drive use pneumatic actuators
powered by the energy of CO
2
gas compressed in special dedicated containers. The
containers are equipped with safety valves. The compressed gas energy release may take
place:
•
Automatically
– when a thermal trip operates. After the trigger temperature has
been reached, the detector in the TAVE thermal trip is destroyed, a pin is
triggered, which
– in turn – triggers a cartridge with compressed CO
2
, the gas fills
up pneumatic actuators and the smoke damper opens.
•
Manually
– if fire has been noticed, a member of staff pushes the manual start
button in the AK alarm box of the given fire zone. The AK box is connected with
the smoke damper by means of a Ø6 mm copper tube. In the AK box there are
cylinders with compressed CO
2
; the gas fills up the system and opens smoke
dampers in the given zone.
•
From the Fire Alarm System (Polish acronym SAP)
– the system is adapted for
connecting 24 V electric signal from SAP.
It is possible to control dampers by means of a “open only” function – “A” type
damper. At that time, after test opening, it is necessary to close the damper manually, from
the roof level.
In the case the double pipe system and a proper actuator type are used, there is the
possibility of carrying out control by means of “open-close” function – “B” type damper. This
type of control by means of a compressor and a PLZ ventilation box, can also carry out the
service function.