Working principle and structure description of intelligent SF6 gas trace moisture tester

Overview of HDWS-II Intelligent SF6 Gas Trace Moisture Tester

This instrument is developed and designed according to the national electric power industry standard DL/T506-2007 "Measurement Method of Insulating Gas Humidity in Sulfur Hexafluoride Electrical Equipment", using imported high-precision dew point sensor and the latest digital circuit control technology. It is a high-precision intelligent instrument for measuring trace moisture content in SF6 gas.

This instrument adopts intelligent self-calibration technology, with wide measuring range, fast response speed, high accuracy, good linearity, and dynamic display of measuring curve. At the same time, this instrument also has an automatic dryer, which can greatly shorten the measuring time.

HDWS-II Intelligent SF6 Gas Trace Moisture Tester Application

This instrument is suitable for measuring the dew point value of SF6 gas. It can also measure the dew point value of air, nitrogen, inert gas and any non-corrosive gas. It is especially suitable for power, petrochemical, metallurgy, environmental protection, scientific research institutes and other departments, with a very high cost performance.

Features of HDWS-II Intelligent SF6 Gas Trace Moisture Tester

(1) High stability: Under severe interference conditions, the measured data can be stabilized within the range of ±0.5°C and has excellent long-term stability and good repeatability.

(2) High precision: It uses imported high-performance dew point sensor and high-speed 12-bit Σ-ΔAD analog-to-digital converter, with the highest resolution reaching 0.1℃, which fully meets the actual measurement requirements. The measurement results are accurate and reliable within the full range, with a wide measurement range, fast response speed, and stable and reliable measurement results.

(3) Intelligence: The sensor probe can automatically calibrate the zero point when powered on, automatically eliminating the system error introduced by zero point drift, and ensuring the accuracy of measurement.

(4) Multiple protections: With oil filter, it is not affected by dust particles and most chemical pollution. It can protect the sensor from oil pollution and is very suitable for use in industrial environments.

(5) Fast and gas-saving: After entering the measurement state, the dew point value measurement time is 3 to 5 minutes.

(6) Powerful functions: 4.7-inch true color touch LCD display, full Chinese operation interface. Directly display dew point value (℃), micro-water value (uL/L), date and time, dynamically display dew point measurement curve. Real-time storage of measurement data, up to 100 sets of measurement data can be stored.

(7) Communication function: The RS232 interface can be connected to the PC serial port to facilitate further data processing by the PC.

(8) Easy to use: It uses self-locking connectors imported from Japan, which are easy to plug and unplug, safe and reliable, and leak-free. The sensitive touch buttons are easy to operate and improve work efficiency. It has a built-in large-capacity rechargeable lithium battery, which is small in size, light in weight, and easy to carry.

HDWS-II Intelligent SF6 Gas Trace Moisture Tester Specifications

(1) Measurement range: Dew point value: -80 ℃ ~ +20 ℃

Micro-water value: 0～19999uL/L

(2) Measurement accuracy: ±0.5℃ (-60℃～+20℃)

±1.0℃（－80℃～－60℃）

(3) Resolution: Dew point value: 0.1℃

Micro water value: 1uL/L

1. Response time (+20℃,0.1Mpa):

                      63% requires 5s, 90% requires 45s (-60℃～＋20℃)

                      63% requires 10s, 90% requires 240s (+20℃～-60℃)

(5) Sampling flow rate: 0.6L/min±20%

(6) Pressure range: 0～1.0 Mpa

(7) Operating temperature: -20℃～+60℃

(8) Ambient humidity: 0～100% RH

(9) Storage temperature: -20℃～+80℃

(10) Charging time: 4 hours

(11) Overall dimensions: 250×150×300mm3

(12) Machine weight: 3.5kg

HDWS-II Intelligent SF6 Gas Trace Moisture Tester Panel Structure

1. The layout of the instrument front panel is shown in Figure 1.

Figure 1 Front panel layout

2. The layout of the instrument's rear panel is shown in Figure 2.

Figure 2 Rear panel layout

Note: Press the stand adjustment buttons on both sides at the same time to adjust the angle of the stand.

Working principle of HDWS-II intelligent SF6 gas trace moisture tester

When the measured gas enters the sampling chamber of the sensor, trace moisture in the gas is adsorbed into the micropores of the sensor. The sensor converts this change into an electrical signal, which is processed by a microprocessor and finally sent to the LCD screen for display.

The micro-water measuring instrument consists of gas circuit part, sensor part, signal processing part and LCD display output part. The instrument test principle diagram is shown in Figure 3.

Figure 3 Test schematic diagram