E2S Warning Signals
Impress House, Mansell Road, Acton, London W3 7QH
www.e2s.com
Tel: +44 (0)208 743 8880
Document No. D210-00-651-IS
Issue 1
13-01-23
Sheet 4 of 13
9)
Earthing
DC sounder units must be connected to an earth. The units
are provided with internal and external earth terminals which
are both located on the terminal chamber section of the unit.
Fig. 3 Internal View of Cover
When using the internal earth terminal ensure that the
stainless steel M4 flat washer is between the incoming earth
wire and the enclosure.
Internal earthing connections should be made to the Internal
Earth terminal in the base of the housing using a ring crimp
terminal to secure the earth conductor under the earth clamp.
The earth conductor should be at least equal in size and
rating to the incoming power conductors. Tighten M4 Earth
screw to 1Nm.
External earthing 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 4mm² in size. Tighten the Earth nut to
3Nm. Please firmly tighten the external grounding terminal so
that the stud does not become loose and lay the ground wire
so that it is not caught by twisting and sagging.
10) Cable Connections
Electrical connections are to be made into the terminal blocks
on the PCBA located in the flameproof enclosure. See
section 7 of this manual for access to the flameproof
enclosure.
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 Live/Neutral or +/-
terminals 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 0.45 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.
11) DC Wiring
A 4-way terminal block is provided on the DC Sounder. There
are 1-off +ve, 1-off -ve, 1-off stage 2 and 1-off stage 3
terminals in total.
Fig. 4 S110 DC Terminals
Refer to D210-06-651 for schematic diagram.
11.1. Stage Switching Polarity (DC Units)
The BExS110D DC sounders have the facility to use either
+ve or
–
ve switching to change the tone to the second and
third stages. Negative switching is the default setting. For
–
ve
switching connect the two headers on the pcb to the left-hand
(marked
–
ve) and centre pins. For +ve switching connect the
headers to the right hand (ve) and the centre pins.
(Refer to Fig. 5)
Fig. 5 Stage Switching Polarity
Refer to D210-06-651 for schematic diagram.