MEDC DB16 - Manual (Page 3)

1.0 INTRODUCTION
This range of loudspeakers, intended for use in potentially explosive atmospheres, has a power rating of either
25W or 30W depending on version.
The unit is available in two versions suitable for use in the following gas/dust groups:
IIB GAS GROUP UNIT* - 30W Ex de IIB T3 Gb (-50°C to +40°C) †
25W Ex de IIB T3 Gb (-50°C to +65°C)
T4 Gb (-50°C to +0°C)
IIC GAS GROUP UNIT - 30W – Ex de IIC T3 Gb (-50°C to +40°C) †
Ex tb IIIC T110°C Db (-50°C to +40°C)
25W – Ex de IIC T3 Gb (-50°C to +65°C)
Ex tb IIIC T110°C Db (-50°C to +65°C)
* IIB unit has nominally 3dB higher output than IIC unit.
† At full power, the 30W unit has nominally 1dB higher output than the 25W unit.
The flamepaths, flare and the body are manufactured completely from a UV stable glass reinforced polyester.
Stainless steel screws and mounting bracket are incorporated thus ensuring a corrosion free product. A tapered
flamepath is used to overcome the problems of assembly of parallel spigot flamepaths.
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 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 in order to maintain the IP rating of the unit.
xi. A suitable sealing washer must be fitted to all glands and stopping plugs fitted into the enclosure.
xii. The internal earth terminal, where fitted, must be used for the equipment grounding and the external
terminal, if available, is for a supplementary bonding connection where local codes or authorities permit
or require such a connection.
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.
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
position and fixed via the other holes.
The fixing holes have been designed to accept an M8 screw or bolt.
© Cooper MEDC 2013 07/13