Wallmounted Microphones

B80 MICROPHONE - ATEX EN13980 94/9/EC

WATERPROOF, BRACKET MOUNTED, INTRINSICALLY SAFE

VT07491 – Certified ATEX approved NSN 5965-99-425-3286

VT07240 – not ATEX approved (no NSN number)

Type B80 Microphone, NSN 5965-99-425-3286 VT07491, conforms with the shock, vibration and waterproofing requirements of DEF-133, Class N1, and SES-5. It is also approved as intrinsically safe ATEX EN13980 94/9/EC for use in flammable atmospheres (Groups 2a, 2c, 2d and 2e) when mounted in a permanent position and installed in accordance with Drawing No. 1563, SIRA Cert. M0953. There is also a non ATEX approved version VT07240.

The microphone inset and switch assembly, housed in a watertight case of cast aluminium Type LM6M, presents a very compact unit suitable for installation in exposed conditions where its robust construction will withstand heavy duty for long periods without attention.

Inside the case a panel is provided with screw terminals for connection to the switched moving coil microphone inset, NSN 5965-99-972-8325, of 25 ohms impedance, and also connections for a relay circuit with the choice of either series or parallel operation.

In addition a slotted shaft protrudes through the centre of this panel which, when turned, changes the switch mechanism from spring return to “OFF”, to click lock in the “ON” position.

Cable entry is normally through a Service Type gland nut of stainless steel, but, if required, as an alternative to the gland nut, the case for Commercial and Intrinsically Safe versions of Type B80 Microphone can be supplied threaded for 19mm (¾”) dia. conduit entry.
All parts are mechanically and electrically interchangeable.