Eaton DB3B Technical Manual

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Contents

1Sounder - dB3B TM264 June 2019 www.eaton.comSounder - DB3BEnglish1.0 IntroductionThis range of sounders, intended for use in potentiallyexplosive gas and dust atmospheres, is available inversions suitable for use in the following gas/dust groups:The range is available in versions suitable for use in eithergas (G) or gas and dust (GD) groups.Noee:N (G) unit has nominally 6dB higher output than(GD) unit.The Ex enclosure is manufactured from a UV stableglass reinforced polyester with a rugged thermoplasticflare. Stainless steel mounting bracket, cover screws andfixings are incorporated throughout thus ensuring a corro-sion free product.An optional Ex e terminal chamber is available (see certifi-cation section for further details).An uncertified version is available for use innon-explosive atmospheres.2.0 General safety messages andwarningsAll instructions and safety messages in this manual mustbe followed to allow safe installation of the device. Thedevice must only be installed and maintained by correctlytrained site personnel/installers.I. To reduce the risk of ignition of hazardousatmospheres and shock, do not apply power tothe device until installation has been completedand the device is fully sealed and secured.II. To reduce the risk of ignition of hazardousatmospheres and shock, keep device tightlyclosed when the circuit is energised.III. Before removing the cover for installation ormaintenance, ensure that the power to the deviceis isolated.IV. Following installation, test the device to ensurecorrect operation.V. Following installation ensure a copyof this manual is made available to alloperating personnel.VI. When installing the device, requirements forselection, installation and operation should bereferred to e.g. IEE Wiring Regulations and the‘National Electrical Code’ in North America.Additional national and/or local requirementsmay also apply.VII. Cable termination should be in accordance withthe specification applying to the required appli-cation. MEDC recommends that all cables andcores should be correctly identified. Please referto the wiring diagram in this manual (or separatediagram provided with the unit).VIII. Ensure that only the correct listed or certifiedcable glands are used and that the assembly isshrouded and correctly earthed.IX. Ensure that only the correct listed or certifiedstopping plugs are used to blank off unusedgland entry points and that the NEMA/IP rating ofthe unit is maintained.X. MEDC recommend the use of a sealingcompound such as HYLOMAR PL32 on thethreads of all glands and stopping plugs and/or asuitable sealing washer in order to maintain theIP rating of the unit.XI. On Exde units, a suitable sealing washer must befitted to all glands and stopping plugs fitted intothe Exe enclosure.XII. The end user or installer shall ensure that thisequipment is protected against external influ-ences which could adversely affect the explosionprotection, or contact the manufacturer if in doubtof the suitability of this equipment in the environ-ment in which it is to be installed.XIII. Ex d UnitsThe internal earth terminal must be used forprotective earthing when required. Do not removethe internal ground strap from the earth terminalwhere fitted.For units with metric entries; gland continuityand earthing may be achieved with an optionalexternal earth plate. If the external plate is fitted,a thread sealing compound such as HYLOMARPL32 must be employed to maintain the IP ratingof the unit.Ex de UnitsThe internal/external earth stud must be usedfor equipment grounding when required. Glandcontinuity is achieved if the optional internal earthplate is fitted.XIV. When installing the device, MEDC recommendsthe use of stainless steel fasteners. Ensure that allnuts, 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 solidobject, not part of the equipment, is a minimumof 40mm from the Ex d flamepath joint.XVII. The purchaser should make themanufacturer aware of any external effects oraggressive substances that the equipment maybe exposed to3.0 InstallationThe unit is mounted via 2 off Ø9mm fixing holes in theU-shaped stirrup/mounting bracket. If required, the unitcan be initially placed via the Ø13mm central hole in thestirrup. 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 optionis available to allow further rotational adjustment tothe unit.The fixing holes have been designed to accept an M8screw or bolt.Access to terminalsOn Ex d versions, the cover is secured with 6 off M5cover screws (4.0mm A/F hexagon key). Once the coverfixings are unscrewed, the cover can be lifted away fromthe enclosure to gain access to the interior. The coverfixings are captive and will remain in the cover.