1. Application
SF6 high-voltage circuit breakers are widely used in power systems. The reliable operation of SF6 high-voltage circuit breakers is critical for power supply departments. The SF6 gas density relay monitors changes in SF? gas density within the circuit breaker, directly impacting operational safety.
The Digital Remote SF6 Density Relay (hereafter referred to as the "relay") is designed to control and monitor SF6 gas density in sealed containers. It is suitable for high/medium-voltage circuit breakers, gas-insulated switchgear (GIS), transformers, and outdoor harsh environments. The relay features three sets of high-precision action contacts to transmit alarm, lockout, or overpressure signals. It also supports real-time remote data transmission (via RS-485) for pressure, temperature, and density monitoring, ensuring data integrity and accuracy.
2. Features
1. Stainless steel fully enclosed housing with excellent waterproofing and corrosion resistance.
2. Remote transmission of gas density signals.
3. Local display of temperature, pressure, and density.
4. Imported temperature-sensitive components with high accuracy and stable compensation.
5. Oil-free design, superior vibration and shock resistance.
6. High-precision contact mechanism using imported components.
7. RS-485 signal transmission for long-distance communication.
3. Technical Specifications
1. Measurement Range:
Relative pressure: -0.1–0.9 MPa; Absolute pressure: 0–1.0 MPa
2. Temperature Accuracy:
0–50°C: ±0.5°C; -40–80°C: ±1.0°C
3. Pressure Accuracy:
0–50°C: ±0.25%
-40–60°C: ±1.0%
4. Density Accuracy:
0–50°C: ±0.5%
-40–60°C: ±1.0%
5. Protection Rating: IP65
6. Sealing Performance: ≤1.0×10?? Pa·m³/s
7. Communication Protocol: Modbus-RTU, Modbus-TCP
8. Operating Temperature: -40°C to +65°C
9. Humidity: ≤95% RH
10. Current Consumption: ≤500 mA
11. Power Supply: 24 VDC (±10%)
12. Terminal Connections:
4. EMS/EMC Performance
1. Electrostatic Discharge Immunity: GB/T 17626.2, Level 4
2. Radiated RF Immunity: GB/T 17626.3, Level 3
3. EFT/Burst Immunity: GB/T 17626.4, Level 4
4. Surge Immunity: GB/T 17626.5, Level 4
5. Conducted RF Immunity: GB/T 17626.6, Level 3
6. Power Frequency Magnetic Field Immunity: GB/T 17626.8, Level 5
7. Pulse Magnetic Field Immunity: GB/T 17626.9, Level 5
8. Damped Oscillatory Magnetic Field Immunity: GB/T 17626.10, Level 5
5. Key Technologies
1. Fully immersed structure for enhanced temperature sensing.
2. Wide-range temperature compensation for pressure fluctuations.
3. Linear correction and compensation for low-humidity environments.
4. Extended calibration cycles and zero-drift mitigation.
5. High integration and miniaturization of SF6 density sensors.
6. Low-error RS-485 communication with anti-interference design.
6. Installation & Usage
1. Install vertically on the equipment interface. Do not open the explosion-proof cap without authorization.
2. Close the valve before installation. Clean surfaces with lint-free cloth/alcohol. Apply sealant to O-rings and tighten nuts with a wrench.
3. Adjust pressure gradually to avoid damaging the relay.
7. Ordering Information
1. Specify model, rated pressure, alarm/lockout pressures, and thread type.
2. Custom requirements must be stated in the contract.
3. Common specifications (customizable):
|
Rated Pressure（Mpa） |
Alarm Pressure（Mpa） |
Lockout Pressure（Mpa） |
|
0.35 |
0.30 |
0.30 |
|
0.35 |
0.32 |
0.30 |
|
0.36 |
0.32 |
0.32 |
|
0.38 |
0.34 |
0.30 |
|
0.40 |
0.30 |
0.30 |
|
0.40 |
0.32 |
0.30 |
|
0.40 |
0.35 |
0.30 |
|
0.40 |
0.35 |
0.35 |
|
0.45 |
0.42 |
0.40 |
|
0.50 |
0.42 |
0.40 |
|
0.50 |
0.45 |
0.40 |
|
0.55 |
0.48 |
0.45 |
|
0.60 |
0.52 |
0.50 |
|
0.60 |
0.55 |
0.50 |
|
0.62 |
0.59 |
0.54 |
|
0.65 |
0.62 |
0.59 |
8. Acceptance & Storage
1. Inspect packaging for damage upon receipt.
2. Verify product integrity, certificates, and manuals.
3. Store in a dry, ventilated area (0–40°C, ≤80% RH).
Drawings
9. System Architecture
1. Field Device: Digital SF6 density relay for monitoring and data transmission.
2. IoT Gateway: Collects data and interfaces with IEDs.
3. Monitoring IED: Analyzes data, generates alarms, and integrates with power systems.
4. The digital remote transmission SF6 density relay is installed on GIS equipment without affecting the original SF6 gas density relay operation or existing on-site maintenance work. It monitors SF6 gas density and transmits SF6 gas density values to the IoT platform via wired IoT communication.
5. SF6 Online Monitoring IED: Deployed in control room panel cabinets. The digital remote transmission SF6 density relays aggregate data to an 8-port RS-485 hub through RS485 interfaces. The hub uploads data to the upper-level management system via RS485 interface. It performs real-time analysis of SF6 gas operating conditions and triggers event alerts based on actual conditions, enabling real-time display, historical data query, aggregation, and export functions for all on-site SF6 gas density monitoring targets. It can also connect to power system networks or platforms using specific communication protocols according to operational requirements.
