1. Testing principle

The KDXJ-8 SF6 gas leakage alarm system adopts the principle of sound velocity, which can quantitatively and real-time measure the SF6 leakage gas content online. It overcomes the shortcomings of traditional measurement methods such as negative corona discharge method and halogen sensor method, which can only qualitatively determine whether the limit is exceeded, and can accurately obtain the SF6 content in the gas.

2. High reliability

The KDXJ-8 SF6 gas leakage alarm system adopts a double differential processing method, effectively overcoming the influence of temperature and humidity on measurement results and eliminating the defects of traditional products.

3. Security

The KDXJ-8 SF6 gas leakage alarm system uses a 24V DC power supply to each collection point, avoiding the use of 220AC power supply in other systems and ensuring the safety of the system.

4. Multi detection function

The KDXJ-8 SF6 gas leakage alarm system mainly detects SF6 gas leakage and oxygen deficiency conditions, and also has auxiliary detection functions for environmental data such as temperature and humidity.
 

5. Early on-site alarm technology

Micro detection technology can issue early on-site alerts, indicate the location of gas leaks, promptly notify personnel in hazardous areas to evacuate, search for and eliminate leakage sources, and protect operating equipment.


6. Fieldbus design

One cable connects all collectors and hosts, which can be separated or combined, and has high on-site adaptability.


7. Multi point networking detection

A single substation can detect up to 120 points simultaneously, meeting the needs of the on-site environment and improving the reliability of detection.
 
8. Remote monitoring function

The KDXJ-8 SF6 gas leakage alarm system adopts the CDT communication protocol and can transmit data to a remote control center. The remote monitoring software included in the system has years of experience in safe operation, is stable and has good scalability, and has functions such as data configuration, graphic configuration, curve analysis, data reporting, and historical data query.


9. Multiple communication methods

Remote communication can use various communication media, including fiber optics, carrier waves, Ethernet, telephone lines, etc.


10. Alarm record query function

The host is equipped with a large capacity data storage, which can store multiple alarm records for easy querying.


11. Historical data recording and querying

The host is equipped with a large capacity data storage, which can store a large amount of measurement data for easy querying.


12. Infrared monitoring function

Optional, the detection staff enters the work area, and automatic voice prompts real-time detection results, enhancing the intuitive feeling of on-site staff.

13. Maintenance free design

Dedicated electrical design, with no adjustable components in the entire machine, high-quality and guaranteed component selection, and excellent anti-interference performance.

Comprehensive technical indicators

work environment
Temperature range: -10 ℃~+50 ℃
Humidity range: ≤ 95% RH
Earthquake level: 7 degrees
Atmospheric pressure: 86kPa~106kPa
SF6 measurement indicators
Measurement range: 0-30000ppmv
Alarm point: can be set within 200~1000ppmv, default 1000ppmv
Measurement error: 0~2000ppm ± 3% FS; 2000~30000ppm ±2%FS
Reference error: ± 5% FS
Repetitive error:<5% FS
Zero drift:<5% FS
Range drift:<5% FS
Oxygen measurement indicators
Detection concentration: 0-25%
Oxygen concentration alarm point: 18%
Oxygen measurement accuracy:<0.4%, O2 at 21%
Power supply and power consumption
Working power supply: AC 220V, 50Hz
Power consumption: Host<25VA, sensor module<5VA
Alarm contact capacity: AC 220V/7A, normally open, normally closed
Fan output capacity: AC 220V/7A, normally open
Other indicators
Temperature measurement range: -25 ℃~+99 ℃
Humidity measurement range: 0-99% RH
Working power supply: AC/DC 100~265V
Alarm output power: AC 220V/10A (can be customized according to requirements)
Fan output power: AC 220V/20A (can be customized according to requirements)
Fan ventilation time setting: adjustable, default is 15MIN/time
Data recording time: 1 month
Communication method: RS-485 bus mode
Communication protocol: General Electric Power Communication Protocol
Insulation performance between shell and power supply:>10M Ω
Electrical strength between the shell and the power supply:>2000V
Electromagnetic compatibility characteristics: Fast transient pulse train GB/T17626.4-1999 Level 3
Lightning (Surge) GB/T17626.5-1999 Level 3

Single technical indicator
1. System host
The host of KDXJ-8 SF6 gas leakage alarm system receives the data transmitted by the collector, synchronously displays it, analyzes and processes it, and makes a judgment after comparing it with fixed standard parameters. At the same time, the host can communicate with the upper PC, receive control commands from the PC, or upload data to the PC for telemetry, remote control, and storage. When the collected data exceeds the set limit, the host automatically runs various control programs and starts peripheral devices to work, including sound and light, voice alarm, ventilation, etc. In addition, the host can measure the temperature and humidity of the environment on its own in order to compensate and correct relevant data.

Installation method: wall mounted or cabinet mounted
Maximum number of collector connections: 31 (adjustable according to user needs)
Dimensions: 800 × 600 × 2360 (mm)
Alarm output mode: normally open contact (passive), RS485 communication
★ Host size: 280mm × 327mm × 76mm
★ SF6 concentration detection range: 0-30000ppm
SF6 gas detection sensitivity: ± 5% set value
★ Oxygen concentration detection range: 0-25%
Oxygen measurement accuracy:<0.5% (0.4%, O2 at 21%)
★ Hypoxia alarm threshold: 18.0% (adjustable)
★ Temperature display range: -20~99 ℃
★ Humidity display range: 0-99% RH
★ Detection points: Standard configuration includes 12 points (expandable to 32 points).
★ Data recording function: automatic recording of alarm events, massive storage, and automatic updates.
★ Alarm output: Relay air contact output, can be connected to RTU, and supports RS485 alarm output.
★ Support RTU remote start fan function.
★ Support infrared human detection technology, automatically start the fan or provide voice prompts.
★ Fan controller: switch type: directly controls the fan power supply; Pulse type: connected to the fan control switch. Optional according to on-site conditions.
★ The fan startup supports multiple modes: timed startup, alarm startup, automatic startup when someone is present, remote startup, manual startup, etc.
★ Multiple forms of host: wall mounted, 3U 19 inch standard chassis; Imitation of Windows interface, user-friendly interface.
★ Support remote transmission and output of measurement data through RS485, such as installing a large LED display screen at the entrance, which allows for immediate viewing of measurement parameters and system operation from a distance. (Users need to choose separately)
Features: Simple and beautiful appearance, rich control functions. LCD display for on-site monitoring of environmental data, with forced fan exhaust, automatic start of fan exhaust in case of alarm, and remote alarm output. Alarm points can be set through the host's built-in function keys, fan timed exhaust function, historical data can be viewed, and communication with the computer can be achieved through RS485. Remote control can also access monitoring data from the host or control fan startup through RTU.

2. SF6 gas and oxygen gas collector
Contains SF6 gas and O2 sensors to detect the content of SF6 gas and O2 in the environment, and the collected data is directly transmitted to the system host for display, analysis, and processing.
Installation method: Fixed in the low position area where SF6 gas is prone to leakage
Dimensions: 181 × 108 × 50 (mm)
Selection principle: SF6 leakage alarm device should meet the design requirements and actual needs of the substation, and SF6 gas and O2 detection should be based on quantitative principles. The quantitative SF6 alarm device using diffusion infrared spectroscopy absorption (also known as infrared laser) detection principle as the sampling method should be selected, and the O2 sensor should adopt an independent high-precision solid-state electrolyte electrochemical sensor.

3. Temperature and humidity collector
Equipped with temperature and humidity sensors, it detects the temperature and relative humidity in the environment, and collects data directly transmitted to the system host for display, analysis, and processing.
Installation method: Fixed in the same environment as SF6 gas and oxygen gas collectors
Dimensions: 181 × 108 × 50 (mm)

4. Monitoring system
Data collection and processing functions;
Event alarm function;
Accident recall function;
Real time curve and historical curve functions;
Data reporting function;
Remote control function;
Equipment information management function.

5. Fan controller
Function: Accept fan control signals from the host and control the start and stop of single-phase (AC220V) fans.
Control power: 220V, 20A
Dimensions: 85 × 120 × 50 (mm)
Applicable fan
Product type: Straight, curved
Working power supply: AC220V/380V
Motor type: ordinary type, explosion-proof type

6. Alarm light
Component composition: police light emitting tube, wiring socket, installation base, decorative cover, controlled by the system host.