|Place of Origin:||China|
|Minimum Order Quantity:||40pcs|
|Price:||Basicly USD 10~15|
|Packaging Details:||Neutral packaging,Size: 42*30*22cm, 40 pieces per carton|
|Delivery Time:||7-14 days|
|Payment Terms:||T/T, Western Union,Paypal|
|Supply Ability:||30000pcs per month|
SAEJ1994 car alarm buzzer,
28VDC car alarm buzzer,
SAEJ1994 car alarm siren
12~48V 97dB fork lift high voltage Ip68 waterproof human voice beep sound car alarm buzzer siren
|Sound pressure||75±4(A)AT 4FT|
|Temperature||-40°C ~ 75°C|
|1.||BJX series is made for truck bus applications in low noise areas.|
|2.||Intelligent models measure the ambient noise level and adjust their output level.|
|3.||create a volume that is safe without being annoying or contributing to noise pollution.|
|4.||Designed to meet all hash conditions and provide splendid durability.|
|5.||Sealed in epoxy for protection against dust, moisture and vibration.|
|6.||Easy to install, and many optional connectors/wire.|
|7.||RoHS compliant, CE certified|
Back-up alarm is a device intended to warn passers-by of a vehicle moving in reverse. They typically produce 1000 Hz pure tone beeps at 97-112 decibels. Matsusaburo Yamaguchi of Yamaguchi Electric Company, Japan, invented the back-up beeper. It was first manufactured as model BA1 in 1963. ISO 6165 describes "audible travel alarms", and ISO 9533 describes how to measure the performance of the alarms.
Although originally intended as a warning device, sometimes these alarms are used on vehicles in a situation where no one is ever likely to be a passerby. (For example, tractors in fields often use them even though no one is ever walking behind the vehicle). The noise, however, can be heard up to 3 kilometres (1.9 mi) away and disturbs residents and people within the vicinity but who will never be within the danger zone of the vehicle itself. In places, like the City of London, this noise pollution has led to a ban on the back-up beeper and alternatives must be used instead.
Back-up beepers are criticized by the public and in scientific literature. Beepers top lists of complaints to government roadbuilders about road construction noise. There is published concern that people become habituated to the ubiquitous noise, diminishing its effectiveness. The normal level of 1000 Hz pure tone beeps at 97-112 decibels, considerably higher than the long-term hearing loss limit of 80 decibelsStrategies such as adjusting the volume according to the ambient noise and changing the tone to include sounds above 1600 Hz and below 800 Hz for improved localization would improve the alarm, but improvements are not cost-effective for the manufacturer and, if implemented by the equipment owner, introduce liability for the owner.
Brains do not adapt to the repetitive and persistent sound of back-up beepers, but have evolved to process natural sounds that dissipate. The sound is perceived as irritating or painful, which breaks concentration.
In some countries, such as the United Kingdom, back-up warning systems using blasts of white noise are becoming more common, and are obligatory for suppliers of some large construction projects. White noise does not have to be as loud as beeps in order to be able to be heard over background noise, and people can more easily hear from which direction the signal comes.
While not addressing the criticism of the type of sound, units exist that moderate the volume based on sensing ambient sound.
4. Competitive Advantage
|Place of Origin:||China|
6. Custom properties
|Product Name:||Back-up alarm||Application:||Outdoor|
7. Product commercial terms
|Minimum Order Quantity:||100pcs|
|Packaging Details:||T/T or western Union|
|Delivery Time:||3,000pcs per month|
|Payment Terms:||10 working days after received your payment|
|Supply Ability:||Packed in box firstly,and then reinforced with neutral packaging for outer packing|