KLAXON SO4 Aluminium Motorised Siren IP55 125dB Low Frequency 900Hz



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SO4 Aluminium Motorised siren IP55 125dB @ 1m

The SO4 is a weatherproof motor driven siren designed for vertical mounting and designed for outdoor warning over small/medium areas.

Manufactured from cast aluminium, it is rugged in construction, has a continuous rating and is built for a long life outdoors.

The sirens incorporate a fractional horse power motor that drives an internal impeller at high RPM forcing air through the slotted front cover creating its unique penetrating sound.

The units offer a single stage alarm when energised but may be pulsed or modulated by simply turning the power on/off to produce the classic ‘wailing’ siren sound. The units are of robust construction and suitable for use in harsh environmental conditions.

The SO4 produces a low frequency sound that is ideally suited for signalling over medium size areas. For maximum coverage it is advised that the unit be raised above the surrounding buildings. Design allows for termination inside the enclosure.


  • Sound output 125db @ 1m
  • Powerful low frequency sound - 900Hz
  • Omni-directional 360° coverage
  • Effective range up to 500m, depending on environment
  • Continuous rating
  • Dustproof and Weatherproof IP55 (when mounted as per instructions)
  • Available in 24VDC, 110VAC/DC and 240VAC/DC
  • Robust aluminium construction


Sound frequency: 900Hz

Protection: IP55

Rating: 20 min

Voltage tolerance: + –10%

Temperature rating (°C): -30 to +45

Cable entry: 20 mm

Construction: Aluminium alloy

Weight: 4.5Kg

Installation Instructions Click Here