Series 842 Air Horns : Introduction
For use with HNL’s single and multi-point annunciators or any application
where a pneumatic audible alarm is required.
- CHOICE OF 5 FREQUENCIES
- 118 dB(A) OUTPUT
- READILY AVAILABLE
The Series 842 Air Horn uses a vibrating brass diaphragm together with
a thermoplastic (or die-cast aluminium) trumpet to provide a sound output of 118dB(A) at
1 metre from the horn. Sound levels fall by 6dB(A) each time the distance
from the horn doubles (e.g. 112dB(A) @ 2m, 106dB(A) @ 4m, etc).
Different frequencies are available enabling different alarms to be identified
by its own unique sound. Alternatively a two tone effect can be achieved
by alternating between two different horns, using HNL’s horn modulator
DS1054.
The air horns are operated from a 0.5 to 1.5 bar pressure supply with
air consumption of typically 15 to 30 Nl/min. Higher pressures can also
be used if the supply is restricted. For operation with a 1.5 to 4 bar
supply a 2mm diameter restriction should be fitted, for operation with
a 4 to 10 bar supply a 1mm diameter restriction should be fitted.
Multiple horns may be used from a single supply to give a wider sound
spread. Two horns used in this way will increase the sound output to 121dB(A)
at 1 metre. A restrictor should be fitted in the supply of each horn to
ensure that in the event of one horn being damaged the supply pressure
to the other(s) will not be affected.
Pneumatic connections are available for 6mm or 1/4” metal, nylon or plastic
tubing. In addition connections are available for PVC covered copper tube.
The horns are designed for site mounting; the trumpet should be tilted
downwards to prevent dust or water ingress. They can be mounted inside
an enclosure provided that venting is sufficient to prevent pressure build
up within the enclosure. The end of the horn should not be obstructed
(minimum clearance of 25mm).
The sound output of the air horns is high so care should be taken to
prevent possible aural damage of operators and other personnel.
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