I.Overview

SF6 gas density relay is an important component used to monitor the change of SF6 gas density in the SF6 switch body during operation. Due to the infrequent action of SF6 gas density relay in field operation, it often has inflexible action, poor contact and other phenomena after a period of time, and some also show that the temperature compensation performance of density relay becomes worse, Sudden change of ambient temperature often leads to misoperation of SF6 density relay. Therefore, DL / T596-1996 preventive test code for power equipment stipulates that each SF6 switch user shall regularly calibrate the SF6 gas density relay.JKMD20 SF6 density relay calibrator is developed according to DL / t259-2012: Calibration Specification for SF6 density relay issued by the national energy administration.

The instrument adopts 7.0 inch color LCD touch screen for human-computer interaction, which is more convenient to operate. Built in high-capacity rechargeable lithium battery pack provides ultra long standby time. The standard USB interface is configured, and the historical data can be exported to the USB flash disk through the interface.

In addition to the calibration of SF6 density relay, the instrument also has the function of calibrating pressure gauge and density gauge. The instrument can automatically detect abnormal conditions during measurement. In case of pipeline leakage, air leakage and insufficient inlet and outlet air pressure, the instrument will automatically stop operation and pop up a warning.

In a closed container, the SF6 gas pressure at a certain temperature can represent the density of SF6 gas. Traditionally, 20 ℃ is the SF6 gas pressure as the standard value. During on-site verification, the measured pressure value shall be converted into its corresponding pressure value at 20 ℃ under different ambient temperatures, so as to judge the performance of SF6 density relay.

II.Technical Indicators

Ø Verification object: alarm 1, alarm 2, locking 1, locking 2, overpressure alarm contact signal

Ø Calibration range: 0 ~ 1MPa (absolute pressure)

Ø Instrument accuracy: grade 0.15

Ø Pressure display resolution: 0.0001mpa

Ø Inlet pressure: 0.9 ~ 1MPa (relative pressure)

Ø External interface: USB (supports USB mobile storage devices no larger than 4GB)

Ø Working environment: temperature - 10 ~ 50 ℃ (the best operating temperature is 5 ~ 50 ℃)

Ø Relative humidity: 5 ~ 90% RH

Ø Display resolution: 800 × 480 (pixel) color touch screen

Ø Storage capacity: 50 groups

Ø Measured contact voltage: DC24V

Ø Temperature acquisition mode: manual / automatic

Ø Air inlet connection: φ 4 butt type quick plug

Ø Air inlet pipe: standard configuration φ 4 / PFA pipe

Ø Measurement connection: φ 4 butt type quick plug

Ø Measuring pipeline: standard configuration φ 4 / PFA pipe

Ø Exhaust connection: φ 4 quick connector

Ø Exhaust pipe: Standard φ 4 / PFA pipe

Ø Mobile power supply: rechargeable lithium battery pack, which can work continuously for 8 hours

Ø Charging voltage: 100 ~ 240VAC, 50 / 60Hz

Ø Overall dimension of host: 325mm long × 275mm wide × Height 140mm

Ø Overall dimension of accessory box: 360mm long × 250mm wide × Height 110mm

Ø Instrument weight: 4.5kg

III.Main Features

1. The density relay calibrator adopts high-performance single chip microcomputer for detection and control, and the core components adopt imported components, with high precision, good repeatability and high reliability.

2. The initial state of 1 ~ 5 groups of contacts of density relay is in any form (normally open or normally closed), and the response value and recovery value of 1 ~ 5 groups of contacts can be measured at the same time.

3. Equipped with color touch LCD screen, it has simple operation and beautiful interface, and all parameters and states are clear at a glance.

4. Automatically complete the pressure measurement and 20 ℃ value conversion, so as to complete the dynamic automatic compensation between pressure and temperature. It also displays the pressure under the measured ambient temperature, the pressure under the ambient temperature at 20 ℃ and the ambient temperature. The problem of difficult field calibration of SF6 gas density relay is completely solved.

5. All testing processes are automatically completed by single chip microcomputer without manual intervention, which avoids cumbersome manual air path adjustment operation.

6. It can store 50 test results at the same time, and has the function of power failure data protection. It can query and print the previous test results at any time.

7. There is no need for constant temperature chamber in the calibration process, and SF6 gas density relay and pressure gauge can be calibrated within any effective temperature range.

8. It is equipped with many types of transition joints. The density relay of most types of switches can be verified on site without disassembly.

9. In addition to the calibration function of density relay, the instrument also has the calibration functions of 20 ℃ pressure gauge and normal temperature pressure gauge.

10. The pressure reducing valve of gas cylinder is professionally designed, which can withstand 15mp (150kg), and the low-pressure output is adjustable. It is suitable for calibration in the metering room with nitrogen as the test gas.