Eaton DB4B Manuel Technique page 5

1.0 Introduction
This range of loudspeakers, intended for use in potentially
explosive gas and dust atmospheres, has a power rating
of up to 25 watts and is available in versions suitable for
use in the following gas/dust groups:
The range is available in versions suitable for use in either
gas (G) or gas and dust (GD) groups.
N ote: (G) unit has nominally 6dB higher output than
(GD) unit.
The Ex enclosure is manufactured from a UV stable
glass reinforced polyester with a rugged thermoplastic
flare. Stainless steel mounting bracket, cover screws
and fixings are incorporated throughout thus ensuring
a corrosion free product.
An optional Ex e terminal chamber is available (see
certification section for further details).
An uncertified version is available for use in non-explosive
atmospheres.
2.0 General safety messages and
warnings
All instructions and safety messages in this manual must
be followed to allow safe installation of the device. The
device must only be installed and maintained by correctly
trained site personnel/installers.
I. To reduce the risk of ignition of hazardous
atmospheres and shock, do not apply power to
the device until installation has been completed
and the device is fully sealed and secured.
II. To reduce the risk of ignition of hazardous
atmospheres and shock, keep device tightly closed
when the circuit is energised.
III. Before removing the cover for installation or
maintenance, ensure that the power to the device
is isolated.
IV. Following installation, test the device to ensure
correct operation.
V. Following installation ensure a copy of this manual
is made available to all operating personnel.
VI. When installing the device, requirements for
selection, installation and operation should be
referred to e.g. IEE Wiring Regulations and the
'National Electrical Code' in North America. Additional
national and/or local requirements may also apply.
VII. Cable termination should be in accordance
with the specification applying to the required
application. MEDC recommends that all cables
and cores should be correctly identified. Please
refer to the wiring diagram in this manual (or
separate diagram provided with the unit).
VIII. Ensure that only the correct listed or certified
cable glands are used and that the assembly is
shrouded and correctly earthed.
IX. Ensure that only the correct listed or certified
stopping plugs are used to blank off unused gland
entry points and that the NEMA/IP rating of the
unit is maintained.
X. MEDC recommend the use of a sealing compound
such as HYLOMAR PL32 on the threads of all
glands and stopping plugs and/or a suitable
sealing washer in order to maintain the IP rating
of the unit.
XI. On Exde units, a suitable sealing washer must be
fitted to all glands and stopping plugs fitted into
the Exe enclosure.
XII. The end user or installer shall ensure that this
equipment is protected against external influences
which could adversely affect the explosion
protection, or contact the manufacturer if in
doubt of the suitability of this equipment in the
environment in which it is to be installed.
XIII. Ex d Units
The internal earth terminal
protective earthing when required. Do not remove
the internal ground strap from the earth terminal.
For units with metric entries; gland continuity and
earthing may be achieved with an optional external
earth plate. If the external plate is fitted, a thread
sealing compound such as HYLOMAR PL32 must
be employed to maintain the IP rating of the unit.
An additional internal stud is provided for a noise-
less (clean) earth connection
or authorities permit or require such a connection.
Ex d e Units
The internal/external earth stud must be used for
equipment grounding when required. Gland conti-
nuity is achieved if the optional internal earth plate
is fitted.
XIV. When installing the device, MEDC recommends
the use of stainless steel fasteners. Ensure that all
nuts, bolts and fixings are secure.
XV. The unit should be positioned such that debris,
dust or water cannot settle in the re-entrant horn.
XVI. The unit should be positioned such that any solid
object, not part of the equipment, is a minimum of
40mm from the Ex d flamepath joint.
XVII. The purchaser should make the manufacturer
aware of any External effects or Aggressive
substances that the equipment may be exposed
to
3.0 Installation
The unit is mounted via 2 off Ø9mm fixing holes in the
U-shaped stirrup/mounting bracket. If required, the unit
can be initially placed via the Ø13mm central hole in the
stirrup. The unit can then be rotated to the required posi-
tion and fixed via the other holes.
If ordered with the unit, a swivel mounting bracket option is
available to allow further rotational adjustment to the unit.
The fixing holes have been designed to accept an M8
screw or bolt.
Access to terminals
On Ex d versions, the cover is secured with 6 off M5
cover screws (4.0mm A/F hexagon key). Once the cover
Loudspeaker - dB4B TM252 November 2023 www.eaton.com
Loudspeaker - DB4B
English
must be used for
where local codes
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