SF6 Relay Working Principle
The intelligent module inside the SF6 relay mainly processes the pressure sensor signal through filtering and operational amplifiers, then converts it into a digital signal through high-precision A/D conversion. Subsequently, the high-performance processor calculates with the temperature signal, can generate analog signals through D/A conversion, and then convert them into 4-20mA current signal output. In addition, the relay can also output multiple signals through the RS485 bus, achieving flexible application of various signals.
The pointer on the dial displays the density value of SF6 gas based on the pressure of SF6 gas after temperature compensation, indicating the standard pressure value at 20℃. When working under rated pressure, if the ambient temperature changes, the pressure of SF6 gas will also change. The temperature compensation unit inside the density relay corrects the pressure changes to ensure the pressure indication of the SF6 gas density remains constant.
Alarm and Interlock Function of SF6 Relay
When working under rated pressure, if the ambient temperature changes or SF6 gas leaks, the internal temperature compensation unit will correct the pressure indication in real-time. When a leakage of SF6 gas causes a pressure drop, the density relay will output an alarm signal through a pair of contacts, indicating the need for refilling. If the pressure continues to drop to the set locking value, the relay will once again output a locking signal through a pair of contacts, triggering the equipment control system to lock, ensuring the safe operation and protection of electrical equipment.
Main Advantages of SF6 Relay
Exquisite appearance, compact size
Made of all stainless steel, with exquisite design and compact size, suitable for various equipment layouts.
High-performance contacts
Gold-plated contacts with large breaking capacity and small contact resistance to ensure stable equipment operation.
Plug-in terminal box
The terminal box is designed for plug-in connection, making it convenient, reliable, and reducing maintenance difficulty.
Main Technical Parameters of SF6 Relay
Measurement range: -0.1—0.9Mpa.
Accuracy grade: 20℃±2℃时1.0级.
Joint thread: M20*1.5 (can be supplied according to customer requirements).
Operating conditions:
Ambient temperature: -30—60℃, atmospheric pressure 86—106Kpa.
Relative humidity: ≤95%.
Insulation strength: AC2000V/1min 50Hz.
Insulation resistance: ≤20MΩ.
Annual leakage rate: Not more than10-15Mpam3/s.
Contact capacity: 30VA, operating voltage: AC 380V.
With its advanced technology and excellent performance, SF6 relay has become an indispensable key component in substation circuit breakers. Its precise monitoring and alarm interlock function in the operation of electrical equipment provide strong support for ensuring the stable and safe operation of equipment.
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