MEDC DB4B, Техническое руководство

Страница: 3 / 40

© Eaton MEDC Ltd 2017 06/17
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.
Note: (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.
x
.
xii. Ex d Units
The internal earth terminal must be used for protective earthing when required. Do not remove the
internal ground strap from the earth terminal.
For units with metric entries; gland continuity and earthing my 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 noiseless (clean) earth connection where local codes 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 continuity is
achieved if the optional internal earth plate is fitted.
x
q
xiii. When installing the device, MEDC recommends the use of stainless steel fasteners. Ensure that all nuts,
bolts and fixings are secure.
xiv. The unit should be positioned such that debris, dust or water cannot settle in the re-entrant horn.
xv. 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
.