The aim of our system is to show an active hearing protection warning sign in critical work areas with flexibly deployable and freely configurable devices. The permanent warning sign quickly loses its effect in workplaces with varying noise level, because workers do not link the actual noise level with the sign, and the sign do not draw the employee’s attention in an appropriate manner. However, the highly visible noise activated warning sign cannot be ignored.
thanks to the separate Sound Level Meter and Display Unit, the measuring microphone can be installed independently of the display, practically anywhere (even in close proximity to the employee).
with the wirelessdisplay the system can be made more flexible, thus the individual units can berelocated (eg. during reorganization or restructuring) at any time (only thepower supply is required).
the calibration ofthe custom built Class 2 Sound Level Meter (according to IEC 61672-1) can beperformed with a standard acoustic calibrator (such as BK 4231).
the microphone can beplaced in accordance with the measurement requirements, in the employee's closesurroundings, away from the sound-reflecting surfaces.
the system processesthe continuous change of the noise level with overlapping up to several minutesand correspondingly controls the displays. So display flickering can be avoidedwhen the noise level is moving around the limit value.
dimmable LED displaylights ensure excellent visibility, according to individual needs, even in highillumination. Due to the larger size the symbol is clearly visible from agreater distance.
the devices aremanufactured individually, fully customized according to the customer’s needs.The displayed symbol and the labels can also be selected individually.
during the handmademanufacturing of our devices great care and attention is paid, the parts areindividually selected.
some parts of thesystem can be flexibly interchanged and expanded by other (optionally moreadvanced) units (eg. LCD display, PC data collector, visualization, etc.), thushybrid systems can be implemented as well.
due to the uniquedevelopment the design is maintenance-specific (in case of continuousmaintenance contract, the warranty is extended to 5 years).
The system implements the real time measurement and data processing of noise loadoccurring at industrial areas. It also indicates the signal warning to the useof personal hearing protection devices – set previously to the interventionlimit value system – at the residence of the employees. The main units of thesystem are the followings:
The unitconsists of a sound level metering device suitable for measuring workplacenoise measurement (with suitable frequency and dynamics range) and acommunication device transmitting the wireless controlling data to the outerdisplays.
The RGBwireless LED display is controlled by the separate logical and driving circuit,processing the signal transmitted by the measuring unit. The illuminatingsignal works according to the followings:
“No hearingprotection necessary” informative sign in case of allowed noise level
Hearing protection issuggested” informative sign in case ofexceeding the lower limit value
(pre-alert status)
“Hearing protection must be worn” informative sign in case of exceeding the upper limit value
(alert status).
Microphone: 1/2” Condenser Microphone with high sensitivity (1 V/µbar) and low distortion, linear signal transmission, 20-20,000 Hz frequency response,Standard XLR to XLR Microphone Cable 1 m, Microphone Stand equipped with a neodymium magnet and windscreen.
Measurements: A-weighted equivalent Sound Pressure Level (LAeq) at time constants of 10 ms, individually adjustable hysteresis signal processing and control.
Accuracy: the instrument meets the requirements of IEC 61672-1:2005 to Class 2 performance, ±2 dB maximum error at temperature range of 0 °C to +40 °C.
Threshold: individually adjustable upper and lower action limits ranging from 40 to 130 dB in 1 dB step size.
Power supply: supply with a nominal 230 V (single phase), allowable voltage fluctuation ±10%, frequency 50/60 Hz.
Location: the unit can be installed via the rear panel with four holes.
Protection: IP65
Dimensions: 300 x 420 x 90 mm (11.8 x 16.5 x 3.5”)
Material: ABS edge banding profile, 3 mm rigid PVC foam back board, 5 mm printed scratch resistant acrylic front panel.
Pictogram: individually chosen graphic design, UV resistant positive and negative screen printing or gluing as required.
Lighting: controlled RGB LED lights are selected corresponding to the unique application requirements.
Power supply: supply with a nominal 230 V (single phase), allowable voltage fluctuation ±10%, frequency 50/60 Hz.
Location: the unit can be installed via the rear panel with four holes.
Protection: IP65
Standard compliance: the display unit meets the requirements of EN 50131-1 and EN 50131-4 standards.
Carrier frequency: 868,1 MHz | Modulation: FSK | Bandwidth: ±90 kHz | Power: max. 10 mW | Communication distance (open area): 500 m (1/4 antenna, direct line of sight) | Communication distance (indoor): 100-150 m | Bit rate: min. 38.400 kb/s
