|Equipment and systems covered by this certificate are as follows:|
The Type YA90C Standard Flameproof Audible Alarm -20oC to +60oC comprises a cylindrical enclosure complete with an external horn flare all manufactured in glass reinforced polyester by compression moulding. The enclosure is fitted with a trumpet arrangement manufactured from flame retardant ABS at the front which is held in position by four M5 by 20mm long stainless steel socket head cap screws of grade A4-80, with brass thread inserts embedded in the body shell. A stainless steel sinter is mounted in the centre of each horn flare to facilitate the transmission of sound energy.
The other end of the body is closed by a spigot cover, secured by six M5 x 20mm long stainless steel socket head cap screws with brass thread inserts embedded in the body shell, a Nitrile O ring is fitted in the flange section of the cover for ingress protection.
The interior of the flameproof housing comprises a driver unit potted into position behind the sinter, together with an circuit board and connecting terminals for 2.5mm2 conductors.
Internal and external earthing facilities are provided by an integral M5 stainless steel stud arrangement.
Cable entry holes are provided as specified on the certified drawings for the accommodation of flameproof cable entry devices, with or without the interposition of a flameproof thread adapter. Unused entries are to be fitted with certified flameproof stopping plugs.
The cable entry devices, thread adapters and stopping plugs shall be suitable for the equipment, the cable and the conditions of use and shall be certified as Equipment (not a Component).
When this unit is intended for use in dust atmospheres the cable entries shall be sealed, in accordance with the applicable installation code of practice, to ensure that the IP6X ingress protection rating is maintained.
When used in an explosive dust atmosphere the cable entry devices shall maintain the ingress protection of the enclosure.
The Sounder may be marked with the alternative ambient temperatures of -60oC to +60oC when successfully pressure tested. In this form the unit is identified as the YA90C LT Flameproof Audible Alarm.
|CONDITIONS OF CERTIFICATION: YES as shown below:|
1. Painting and surface finishes, other than those applied by the manufacturer, are not permitted.
2. When this unit is intended for use in dust atmospheres the cable entries shall be sealed, in accordance with the applicable installation code of practice, to ensure that the IP6X ingress protection rating is maintained.