Visibility meter, visibility detector, visibility measuring instrument, visibility analyzer

British Biral visibility detectorDF320

To obtain a measurement height, an ICAO ruler is required, and the DF320 visibility gauge uses a 4-meter brittle tilt rod to adjust the measurement height of the probe body.

The DF320 visibility detector consists of a white light source and an axial receiver. The intersection of the visible areas of the light source and receiver is determined by the analysis container, and suspended particles in the container scatter light in all directions.

The meteorological optical distance (MOR) is determined based on the flux measured by forward scattered light. The weak spiritual density is due to the continuous decrease in visibility (rain, snow, fog), and the measurement of visibility is achieved by modulating the distribution frequency with low frequencies in a large container, which can compare to all scintillation effects.

Operation of visibility detector DF320:
data collection
Every 0.5 seconds, the instrument measures the scattered energy in the atmosphere through a photodiode and a 12 bit converter, while undergoing automatic compensation.
data processing
Eliminate erroneous data (median) and unexpected abnormal variables, regularize emission flux measurements, and obtain cyclic average data from 30 seconds to 10 minutes. The tested Kalman conjecture takes into account the impact of noise and inconsistent measurements.
Measurement confirmation and control factors
The power supply supports voltage, lamp voltage, lamp operation, luminous flux, receiver dust pollution, measurement quality, probe body temperature, effectiveness of parameters and software, maintenance and calibration time. The self diagnostic process can be applied to local IHM, and alarms and alerts can be sent to remote controllers.
Bidirectional data transmission
Local point-to-point: RS-2321200-19200 baud rate
※ Remote point-to-point (CIBUS standard): FSK optoelectronic isolation modem, 1200 baud rate, optional
※ Local/remote multi-point: Optical isolation RS-485, 51200-19200 Bonte aluminum, optional



Visibility meter DF320 user interface:
There is a good local user interface (16 digit LCD, three key keyboard) that allows you to view and control data or information, as well as perform maintenance or calibration, and of course, modify parameters. These functions can also be connected to the computer through a serial cable for operation.

Visibility meter DF320 mechanical:
The mechanical optical probe body, partition, cover, and aperture are all placed in a "top-down" waterproof structure, which can effectively protect the instrument and prevent particles from being blown horizontally. An efficient heating system (optional) can accommodate the accumulation of blizzards or ice, allowing the instrument to be used in extremely harsh environments. The mechanical design with a large opening can avoid the influence of shadows or wind direction on the measurement. The transmitter probe and receiver are designed separately, and the hinged mounting support and intuitive user interface make installation and operation very easy for users. The sensor can provide short-term service outside.


Technical performance parameters of visibility meter DF320:
Measurement principle: Forward scattering of 20Hz phase change modulation light source
350-900 nanometer halogen white light balance lamp
Light source lifespan: 25000 hours (3 years)
Analysis container capacity: 10 liters
Analyzing the height of the container from the ground: 4.5 meters to 4 meters (on-site adjustment)
Scattering angle: 20 ° -50 °
Scattering coefficient acquisition time: 0.5 seconds
MOR average cycle: 30 seconds to 10 minutes, users can choose
MOR measurement range: 10 meters to 70 kilometers, with a resolution of 1 meter
MOR accuracy: ± 10%, measuring 90% of 5 kilometers; ± 15%, 5 kilometers to 20 kilometers; ± 25%, greater than 20 kilometers
Flux measurement error: ± 2%
Power supply: 230V ± 10%, 50Hz, 100VA (280VA, high-power heating, optional)
Working environment temperature: -15-50 ℃ (-30-55 ℃, high-power heating, optional)
Working environment humidity: 0-100%
Working environment wind speed: 60 meters per second
Weight: 45 kilograms
Height: 1700-4200 millimeters
Electronic compatibility: NFEN 50081-1, NFEN 50082-1 (CE)
Attachment: Calibration Tool
Background light sensor: LUCIA 320