European Safety Systems Ltd.
Impress House, Mansell Road, Acton, London W3 7QH
www.e2s.com
Tel: +44 (0)208 743 8880
Document No. D211-00-671-IS
Issue 3
20-08-22
Sheet 4 of 8
- - + +
External
Earth
Internal
Earth
2-off ½” NPT thread & 1-off ¾” NPT thread
If a high IP (Ingress Protection) rating is required then a
suitable sealing washer must be fitted under the cable glands
or blanking plugs.
For use in explosive dust atmospheres, a minimum ingress
protection rating of IP6X must be maintained.
For use in explosive gas atmospheres, a minimum ingress
protection rating of IP54 must be maintained.
NPT plugs should be greased before insertion.
8) Cable Connections
Electrical connections are to be made into the terminal blocks
on the PCBAs located in the enclosures. See section 6 of this
manual for access to the enclosures.
The Sounder and Beacon are supplied connected by default.
In order to power the beacon and sounder separately, the link
wires between the units must be disconnected.
Wires having a cross sectional area between 0.5 mm² to
2.5mm² can be connected to each terminal way. If an input
and output wire is required the 2-off +/- terminals of the
beacon or 3-off +/- terminals of the sounder can be used. If
fitting 2-off wires to one terminal way the sum of the 2-off
wires must be a maximum cross sectional area of 2.5mm².
Strip wires to 8mm. Wires may also be fitted using ferrules.
Terminal screws need to be tightened down with a tightening
torque of 0.56 Nm / 5 Lb-in. When connecting wires to the
terminals great care should be taken to dress the wires so that
when the cover is inserted into the chamber the wires do not
exert excess pressure on the terminal blocks. This is
particularly important when using cables with large cross
sectional areas such as 2.5mm².
9) Wiring
The beacon is powered via factory installed wires connected
to the alarm horn. The wires connecting the alarm horn and
strobe can be removed if the user wishes to power the strobe
separately. For further wiring schematics refer to document
D211-06-651
Fig. 4 Terminals
10) Earthing
The beacon bas has both internal and external earth points,
(please see fig 5). The sounder PCBA also has earth terminals,
(see fig 4).
Internal earthing connections should be made to the internal
earth point on the beacon, (please see fig 5). The earth
conductor should be at least equal in size and rating to the
incoming power conductors. The internal earth bonding wires
connect the covers to the internal earth points in the bases.
External earth connections should be made to the M5 earth
stud, using a ring crimp terminal to secure the earth conductor
to the earth stud. The external earth conductor should be at
least 4mm
2
in size. The external earth crimp ring should be
located between the two M5 plain washers provided and
securely locked down with the M5 spring washer and M5 nut.
Fig. 5 Earth locations
11) End Of Line Monitoring
On DxC2 DC units, dc reverse line monitoring can be used if
required. All DC units have a blocking diode fitted in their supply
input lines. An end of line monitoring resistor can be connected
across the +ve and –ve terminals. If an end of line resistor is
used it must have the following values:-
Min. Resistance
Min. Power
3.9KΩ
0.5W
1KΩ
2W
The resistor must be connected directly across the +ve and
-ve terminals of the PCBA, as shown in the following diagrams.
Whilst keeping its leads as short as possible, a spacing of at
least 1/16 inch (1.58mm) must be provided through air and over
surfaces between uninsulated live parts.
Fig. 6a End of Line Resistor Forming