External alarm siren | blue | 12 V DC | 115 dB

Technical Specifications

Signal type: Audible and visual
Optical indicators: 2 high-power LED diodes
Light color: Blue
Alarm tones: 2 selectable tones
Sound intensity: 115 dB (at 1 m)
Sound duration: selectable – 1 min, 4 min, or 16 min
Light indication duration: selectable – 1 min, 4 min, or unlimited
LED indication modes:

Flashing light – standby mode

Double flash every 5 s – tamper detection

Triple flash every 5 s – active alarm with siren
Tamper protection: triggers alarm when cover is removed or device is detached from wall
Operating voltage: 12 V DC
Current consumption during alarm: ≤ 0.5 A
Backup battery: none (model without accumulator)
Mechanical resistance: very high (70 % polycarbonate, 30 % ABS)
Dimensions (W × H × D): 155 × 250 × 67 mm
Operating temperature: −40 °C … +70 °C
Environmental compliance: RoHS

Functions and Operation

The MR300BL combines a powerful 115 dB audible siren with bright LED visual alerts for maximum visibility.
Two alarm tones are available to select the preferred warning sound.
A built-in tamper protection mechanism detects any attempt to open or remove the siren.
LED indicators clearly display system status:

Triple flash: alarm active

Double flash: tamper attempt

Steady flash: standby mode

Applications

Residential houses, cottages, and private properties – as an external siren solution

Commercial buildings, warehouses, shops, and offices – for intrusion alerts

Engineers and installers – compatible with 12 V security systems

Industrial facilities – for strong visual and audible signaling in noisy environments

Advantages

Powerful 115 dB alarm sound

Weather-resistant, RoHS-compliant construction

Reliable anti-tamper protection

Easy installation, selectable operating time

Wide temperature range (−40 °C … +70 °C)

Durable polycarbonate/ABS housing

Disadvantages

No built-in backup battery – requires external power

No sound level adjustment (fixed 115 dB volume)