Dräger Flame 5000, Техническое руководство

Страница: 19 / 35

Installation of the Dräger Flame Detector 5000
19
body should then be fi tted to the mounting bracket. The bolts fi t into key slots in the bracket. Twist the enclosure
to locate the bolts; these are then tightened using a 6mm Allen key.
Electrical Installation
In order to maintain compliance with the EMC regulations it is essential the electrical installation be engineered
correctly.
It is advisable to check the detection locations, prior to fabrication of the mounting supports, as changes are •
frequently made during construction at site.
Detector cabling must be segregated from cables carrying high-speed data or high energy and/or high frequency
•
signals and other forms electrical interference.
The detector requires a clear unobstructed view of the local hazard. In order to avoid local obstructions, such as
•
pipe-work and cable trays, a 2m helix should be allowed in the detector cabling.
The detector should only be installed just prior to commissioning. Experience shows that the detector can be
•
damaged due to cable testing operations (Insulation Tests, etc)
Isolate all associated power supplies. Ensure that they remain OFF until required for commissioning. 1.
The threaded fl ame path of the enclosure cover and body must be protected from damage during installation. Any 2.
such damage can destroy the validity of the enclosure.
The electronics subassembly shall be protected from mechanical damage and external sources of EMI such as
3.
X-rays, RFI and electrostatic discharge.
The enclosure’s external earth stud should be connected to a local earth point.
4.
Remove the blanking plug(s) from the enclosure body gland entries. 5.
Fit approved cable glands using sealing washers to maintain ingress protection. 6.
Prepare the cable tails. The cable screens should be cut back to the crotch at the detector and insulated from 7.
contact with the enclosure or any other local earth. The twist in each pairs should be maintained to within 1”
(25mm) of the termination. Cable tails should be 8” (200mm) long.
Where plastic junction boxes are used the cable screens (shields) should be maintained to within 1” (25mm) of
8.
the termination and fully insulated.
Where unscreened cables are used for panel wiring, then all cables must be suitably twisted into pairs and video
9.
cables should be segregated from other signal sources.
All cable screens (shields) should be connected to the local clean earth at the control panel. The screens and
10.
twisted pairs should be maintained to within 1” (25mm) of the terminations.