Sirens installation should also pay attention to the wind direction
The Sirens is usually installed over 35 to 40 feet (11 to 12 meters) above the ground. If the Sirens is 35 feet below the ground, the intensity of the sound in the near range will increase, but the effective range of the sound will be reduced. On the contrary, if the height of 40 feet above the ground, the effective range of the sound will increase, but the sound may be skipped near the Sirens near the area, the Sirens itself has a relatively high installation, generally high ≥ 0.8 meters, ≤ 2.0 meters Range is appropriate The sound of the siren can cause the Sirens to be optimized in the community. Experience shows that a person with a normal hearing can hear at least the same amount of sound as the ambient noise. Experience also tells us that the factory area surrounding noise is usually 90 dB. Therefore, for a factory area can hear the signal strength of the signal is also about equal to 90 dB.
In this case, signals at any location below 90 dB are considered not to be within the valid range of the Sirens. Wind speed and wind direction also often affect the sound coming from the Sirens. Therefore, in the choice of an Sirens system to choose the installation site, the prevailing wind direction should also be considered within the scope. For example, if the prevailing winds are from the West, we can install the siren at the west of the siren's effective range. Other factors to consider include the availability of power supplies, ease of installation and maintenance, and the height of the surrounding obstacles. Wind speed and wind direction: they often affect the sound from the Sirens device, the prevailing wind direction should also be considered within the scope. For example, if the prevailing winds are from the West, we can install the siren at the west of the siren's effective range.
Why is the Sirens line and sub-line, take the methane Sirens, the middle of what is the difference? Bus and sub-line is the main way of wiring different, most of the sub-line-type instrument for the three-wire system, the detector and the host channel are one by one, each detector must be connected to a three-core to the host. Detection of flammable and detect toxic Although the price difference between the poor, but the use is certainly not the same. And industrial safety norms marked on the plain, ammonia is a toxic gas, ammonia must be tested the toxicity, that is, according to ammonia ppm detection. In some places, if the user is installed flammable ammonia Sirens, then the local quality supervision is not check the past, so the user in the election of ammonia Sirens when we must pay attention. For safety equipment, the ammonia Sirens is not only a device, but also a safety device, is a protective work of industrial safety, so I suggest that users do not just because of its cheap and buy, to our personal Security is responsible. Purchase time to see the relevant hard technical parameters.
For most of the bus-type Sirens, for the four-wire connection, four-wire connection by the host cited a main line out, and then the various detectors were parallel to the main line above. For the choice of the Sirens bus and sub-line, mainly by the user to select the number of detectors to determine the number of detectors for more than six, then the general use of the bus Sirens. If you have less than six, you must use sub-line Sirens. Detector to avoid high concentrations of ammonia impact, so easy to poison the detector; to avoid frequent power, unstable power, so easy to damage the instrument. Often the detector is wiped to prevent dust from clogging the sensor. The need for detector calibration, to prevent the detector to detect data wandering, improve the accuracy of the detector data. Detector is regularly calibrated, components are protected, and the service life is long. Detector calibration is generally used in the last year or six months after the inspection environment according to the site. The Sirens detection environment is generally affected by dust, corrosion of ammonia and other related effects, the environment is relatively poor, so the user in the use of the time to the Sirens on the maintenance, so as to maximize the efficiency of the Sirens detection and long life, The cost.