WHAT TO CONSIDER WHEN
SELECTING A BEACON Selecting the right beacon needs to take key factors into consideration to make the most efficient use of the unit selected for an application. Whether if it’s considering key environmental factors, choosing between different types of beacons and indication variables, an informed understanding will help you make the right selection. When choosing a beacon for an application consider the following environmental related factors: •
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Is the beacon to be used in a safe atmosphere or potentially explosive atmosphere such as refineries, chemical plants, mine sites etc. For the beacons used in operations where the atmosphere is flammable/ignitable, make sure the beacons adhere to relevant standards The ambient level of noise (dB) and/or existing light (J) at site The light output required from a beacon (measured in joules) The duration that the beacon must operate IP rating of the beacon The electrical supply available
The environment in which the warning signal is to be installed will determine the product selection. As an example, consider that a signal designed for heavy industrial applications, incorporating a high decibel (dB) rating & light intensity would not be suitable for local signalling at a control panel. Alternatively, a low dB & light intensity would be ineffective for a large factory environment. Beacons are available in different types which offer varied advantages in their use. The five main types include: ROTATING BEACONS: Includes a parabolic reflector that’s driven by an electric motor which revolves around a continuously illuminated lamp on the vertical axis of the beacon creating a powerful beam of light travelling through 360 degrees. In general, this type of
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beacon has a greater degree of light output than other models, but this is reduced as the parabolic reflector only illuminates one given point at a time. FLASHING FILAMENT BEACONS: These units are operated through an internal circuit, which simply cycles the lamp on and off. The light output is generally lower as it takes longer for the lamp to fully illuminate itself however the output can be improved using a Dioptric (Fresnel) lens which is placed over the lamp capturing the light emitted, magnifying, and directing it to increase the brightness of the visual signal. In terms of providing light coverage this type of beacon is efficient as it illuminates the whole surface of the beacon constantly through 360-degrees. STATIC FILAMENT (CONTINUOUS) BEACONS: These units are identical to flashing filament beacons with the exception that they do not operate through an on and off cycle. When the unit is energised the light source stays permanently ‘on’, until turned off. The main advantage of this type of beacon is that the light can be controlled by a separate source example a relay or Programmable Logic Controller (PLC). XENON (STROBE) BEACONS: A discharge capacitor operating through a converter circuit ignites xenon gas, which ignites instantaneously, inside a tube creating a bright flash of light. In some Moflash models supplied by NHP, a ‘Double Flash’ option is also available which extends the signal duration making it more noticeable to the human eye. Xenon’s have the added advantage of low current consumption combined with long life; the tube life is approximately 5 million flashes. These units are highly efficient, incorporating a 360-degree light output with the brightest and most effective visuals. LED BEACONS: LED ‘light emitting diode’ beacons are ideally suited for long life applications typically achieving 100,000 hours of service. LED models in
