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Sight Selection Guide


sight_selection_guide

Selection & Application

The environment in which the beacon is to be installed will determine the product type and light intensity. Thus a beacon designed for industrial use incorporating a very high light output would not be suitable for local signalling at a control panel. Alternatively a low light output beacon would be ineffective for large factory equipment.

Generally Moflash can supply beacons for all types of applications. Listed below are some of the main market areas.

Automotive

Warning beacons for use on automobiles (commercial and private), agriculture/off road vehicles and forklift trucks, etc.

Industrial

Warning beacons for heavy duty, high light output applications such as foundries, factory shopfloors, large warehouses, etc.

sight_selection_guideCommercial

Warning beacons for light duty, low to medium light output to give local indication such as offices, hospitals and schools. Also suitable for fire and security applications.

Explosion protected

Warning beacons for use in potentially explosive environments such as oil rigs, refineries and mines, etc.

Signalling DevicesEnvironmental factors determining selection

 

  • Safe atmosphere or potentially explosive atmosphere
  • The ambient level of existing light
  • The light output required from the beacon
  • The duration the beacon has to operate
  • The IP rating of the beacon
  • The electrical supply available

Types of visual warning beacons available

Signalling DevicesMoflash manufactures five different types of visual warning beacons.

Rotating beacons

A parabolic reflector, driven by an electric motor, revolves around a continuously illuminated lamp on the vertical axis of the beacon creating a powerful beam of light travelling through 360 degrees. These units are available with either a filament or a tungsten halogen lamp.

In general this type of beacon has a greater degree of light output than other models but this is reduced as the parabolic reflector only lluminates one given point at a time. 

Flashing filament beacons

Signalling DevicesOperating through an internal circuit, which simply cycles the lamp on, and off. These types of beacons generally give a much lower light output as it takes longer for the lamp to fully illuminate itself. These units are available with either a filament or tungsten halogen lamp. The light output can be improved by the use of a Dioptric (Fresnal) 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 light coverage this type of beacon is more 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 i.e. a control panel, giving the unit more flexibility. These units are available with either a filament of tungsten halogen lamp.

Xenon (Strobe) beacons

Signalling DevicesA discharge capacitor operating through a converter circuit ignites xenon gas inside a tube creating a brilliant flash of light. Xenon gas ignites virtually instantaneously so maximum brightness is obtained immediately. In some Moflash models a 'Double Flash' option is also available which extends the signal duration making it more noticeable to the human eye.

Xenons have the added advantage of low current consumption combined with long life. The tube life of a xenon beacon is approximately 5 million flashes. These units are the most efficient available, incorporating a 360 degree light output with the brightest and most effective visual gear.

LED beacons

LED 'light emitting diode' beacons are ideally suited for long life applications typically achieving 100,000 hours of service. The 125 series LED beacon incorporates 48 LEDs in one enclosure and has two modes of operation, static and flashing (switch selectable on the pcb). The 201/200 and 401/400 series LED beacons incorporate 144 LEDs in one enclosure and has three modes of operation, static, flashing and rotating (switch selectable on the pcb).

 

moflash_MOR200

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Visual warning beacons communicate their message through two (sometimes three) variables:

  • Level of brightness
  • The colour of the beacon dome
  • Audibility if fitted with the audible signal

Level of brightness

moflash_Moled125Brightness depends on the type of beacon chosen and the rated output of the unit i.e. Watts and Joules, the distance that the signal is observed from and the dome colour of the beacon used. In general, if the viewing distance is doubled the light intensity observed is reduced to a quarter and if the distance is quadrupled, the light intensity is reduced to a sixteenth.

Beacon dome colours

The intensity of the light can be greatly reduced as it passes through the dome of the beacon.

The extent of this reduction is dependant upon:

  • The type of light source used i.e. conventional filament (incandescent) lamp, tungsten halogen lamp or a xenon tube
  • The colour of the beacon dome that is used
  • moflash_MOX250The table below gives an indiction of the percentage of light that will pass through the beacon dome for different light sources and dome colours
Colour Filament
Halogen
Xenon 
clear CLEAR
100% 100% 100%
amber AMBER
70% 70% 70%
red RED 30% 27% 23%
green GREEN 12% 15% 25%
blue BLUE 8% 10% 13%
 Different dome colours are used to convey different messages to the observer
red RED - Serious danger act now
amber AMBER - Warning proceed with care
green GREEN - OK, proceed as normal
blue BLUE - Specific process notice / warning

moflash-MOX200

Generally, Green colour beacons are used by Doctors and Veterinarians and Blue beacons for the Police and Fire departments.

Audibility

Simply producing an audible sound when the beacon is illuminated. This is of particular use in low level noisy environments if the warning light is obstructed from direct viewing, or as a back up warning should the lamp fail.

Siting and maintenance of visual warning beacons

moflash-MOR88The siting and maintenance of visual warning beacons is as important as their selection and application. When installing a light, care should be taken to position it in the most effective place, if possible, to allow for all round light dispersion. However, the following parameters should be noted.

  • Always ensure that there is air movement around the beacon enclosures as in normal operation, this will warm up due to heat emitted from the light source. High power models can be quite hot over an extended period of time, therefore, avoid sitting the light under gantries, overhangs or in tight enclosed spaces with restricted air movement.
  • Regularly clean the dome of the beacon, as this will maintain optimum light output and reduce heat build up. All domes produced by Moflash are manufactured from ‘UV’ stable polycarbonate plastic. Therefore do not clean with petroleum based cleaners.
  • Areas of vibration should be avoided. If this is not possible then our anti-vibration mount 50080 should be used.
  • In general it is not recommended that beacons be mounted directly onto conduit tubing without the use of a conduit junction box or bracket. 
  • moflash-MOR400To maintain the IP rating of the units the beacon must be mounted with the dome upwards and fully locked onto the base assembly. The beacon should also be suitably sealed at the point of connection using the correct cable glands.
  • Xenon tube failures, unlike filament lamps, which fail immediately, deteriorate very slowly. Irregular or erratic flashing will indicate the pending failure of the tube. Once this is recognised the tube should be replaced as soon as possible. Failure to do so will result in electronic damage to the printed circuit board.

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