Micropack FDS301 - 3.4.2 Electrical Installation

3.42
Electrical
In order to maintain compliance with the EMC regulations it is essential the electrical installation
be engineered correctly.
This document is strictly private and confidential, reproduction without Micropack approval is prohibited. © Micropack Engineering Ltd, 2015
Notes
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 fitted just prior to commissioning
the detector. Experience shows that the detector can be damaged due to cable testing
operations (Insulation Tests, etc)
1
Isolate all associated power supplies. Ensure that they remain OFF until required for
commissioning.
2
The threaded flame path of the enclosure cover and body must be protected from damage
during installation. Any such damage can destroy the validity of the enclosure.
3
The electronics subassembly shall be protected from mechanical damage and external sources
of EMI such as X-rays, RFI and electrostatic discharge.
4 The enclosures external earth stud should be connected to a local earth point.
5 Remove the blanking plug(s) from the enclosure body gland entries.
6 Fit approved cable glands.
7
Prepare the cable tails. The cable screens should be cut back to the crotch at the detector and
insulated from 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.
8
Where plastic junction boxes are used the cable screens (shield) should be maintained to within
1” (25mm) of the termination and fully insulated.
9
Where unscreened cables are used for panel wiring, then all cables must be suitably twisted into
pairs and video cables should be segregated from other signal sources.
10
All cable screens (shield) should be connected to the local clean earth at the control panel. The
screens and twisted pairs should be maintained to within 1” (25.4mm) of the terminations.
FDS301 Flame Detector FDS301 Safety and Technical Manual
16
Ref: 2200.5009 Rev: 2.3 ECN 4434