The JW-VT100M Split-Type Atmospheric Transmissometer is an optical measurement instrument designed for atmospheric transmittance testing, road visibility measurement, and tunnel smoke concentration assessment.
Using a transmitter-and-receiver configuration, the instrument measures light transmission along an optical path and provides measurement results for road and tunnel environmental monitoring.
With a visibility measurement range of 2–10,000 m, transmittance range of 0–100%, LCD display, local data storage, and RS232/RS485/USB communication interfaces, the instrument is suitable for engineering inspections, tunnel acceptance testing, and atmospheric visibility assessment.
The system supports both mobile and fixed installation arrangements.
1. Product Overview
What Is an Atmospheric Transmissometer?
An atmospheric transmissometer is an optical instrument that measures the amount of light transmitted through a defined atmospheric path.
When light travels through fog, haze, smoke, or other airborne particles, a portion of the light is scattered or absorbed. By measuring the reduction in transmitted light, a transmissometer can assess atmospheric optical transmission.
The JW-VT100M uses this measurement principle to provide atmospheric transmittance, visibility, and optical smoke concentration measurements.
Split-Type Measurement Configuration
The instrument consists of three main components:
Optical transmitter
Optical receiver
Measurement and data-processing software
The transmitter and receiver are positioned across the measurement path.
An optical alignment device assists installation and commissioning. Measurement values can be displayed on the LCD and recorded using the accompanying PC software.
Unlike a forward-scattering visibility sensor, a transmissometer measures light transmission along an optical path between separated optical components.
This configuration is particularly relevant to tunnel smoke inspection and optical transmittance testing.
2. Technical Specifications
Parameter
Specification
Product Model
JW-VT100M
Instrument Type
Split-Type Atmospheric Transmissometer
Measurement Principle
Optical Transmittance
Visibility Range (VI)
2–10,000 m
Transmittance Range (T)
0–100%
Smoke Concentration (K)
0–35 × 10⁻³ m⁻¹*
Transmittance Measurement Error
±2%
Display
LCD, Digital and Character Display
Operating Temperature
-55°C to +65°C
Operating Humidity
0–100% RH
Communication Interfaces
RS232 / RS485 / USB
AC Power Supply
220 V AC ±15%, 50 Hz
DC Power Supply
12 V DC
Local Data Storage
More Than 72 Hours
Protection Rating
IP65
Installation
Mobile or Fixed
Total Weight
18 kg, Including Instrument, Case and Mounting Support
*The smoke concentration exponent and unit should be confirmed against the official technical manual before publication.
3. Working Principle of the Optical Transmissometer
The JW-VT100M uses the optical transmittance principle to evaluate the transmission of light through the atmosphere.
The measurement process includes:
Step 1: Light Transmission
The optical transmitter directs light toward the receiver across the measurement path.
Step 2: Atmospheric Attenuation
Suspended particles, such as fog droplets, dust, or smoke, reduce the amount of light reaching the receiver.
Step 3: Optical Signal Detection
The receiver detects the transmitted optical signal, allowing the system to determine atmospheric transmittance.
Step 4: Measurement Processing
The instrument processes the optical measurement to provide relevant visibility and smoke concentration results.
Step 5: Data Display and Storage
Measurement results are displayed through the LCD and can be recorded using the PC software for subsequent analysis.
Atmospheric transmittance represents the proportion of light transmitted through the optical path.
The relationship between transmission, optical extinction, and visibility depends on the optical measurement geometry and applicable calculation method.
4. Main Applications
4.1 Road Visibility Measurement
Low visibility caused by fog, haze, and other atmospheric conditions creates challenges for road inspection and traffic safety assessment.
The JW-VT100M can measure road visibility under different weather conditions.
Typical applications include:
Highway visibility inspection
Road environmental measurement
Fog and haze visibility assessment
Visibility data collection for engineering investigations
Request a quotation or contact our team to discuss your tunnel and road visibility measurement project.
FAQ
Q
1. What does the JW-VT100M measure?
A
It measures atmospheric transmittance, visibility, and optical smoke concentration.
Q
2. What is the visibility measurement range?
A
The specified visibility measurement range is 2–10,000 m.
Q
3. Can the instrument be used for tunnel acceptance testing?
A
The instrument is intended for tunnel smoke concentration measurement and engineering acceptance applications. Its suitability for a particular project depends on the applicable testing requirements.
Q
4. Does the transmissometer support data export?
A
Yes. Measurement data can be stored and exported to Excel format through the PC software.
Q
5. What communication interfaces are available?
A
The instrument supports RS232, RS485, and USB interfaces.
Q
6. Can the instrument be installed permanently?
A
Both mobile and fixed installation configurations are supported.
Q
7. Is this instrument the same as a forward-scattering visibility sensor?
A
No. A transmissometer measures optical transmission between a transmitter and a receiver, while a forward-scattering sensor measures scattered light to estimate visibility.
Q
8. Does the JW-VT100M measure CO concentration?
A
CO measurement is not specified for this model. For projects requiring CO measurement, refer to the Portable Tunnel Transmittance Meter.
+86 13520127780 
info@jingelway.com
