HF-ET-807 Transmission Line Parameter Analyzer

Transmission Line Parameter Test System

The HF-ET-807 Transmission Line Parameter Test System integrates special test power supply, measuring instruments and mathematical models. It suppresses interference and ensures equipment safety, enabling fast, convenient and accurate measurement of power‑frequency parameters for transmission lines.

Product Features

1. Rapid and accurate measurement of positive‑sequence capacitance, positive‑sequence impedance, zero‑sequence capacitance and zero‑sequence impedance. It can also measure mutual inductance and coupling capacitance between lines (line DC resistance shall be measured by dedicated DC resistance tester).
2. Strong anti‑interference capability. It performs accurate measurement when the ratio of heterofrequency signal to power‑frequency interference signal reaches 1:10.
3. Simple external wiring. Complete all line‑parameter measurements with one‑time connection to down‑lead wires of tested line.
4. Built‑in DSP digital‑signal processor integrates test power supply, meter and computing model. Compact single‑unit design replaces bulky cabinet‑style equipment. Adopts large‑size Chinese‑character LCD, rotary‑mouse operation and built‑in micro‑printer for easy report output.
5. Short test cycle. The unit automatically controls test mode, voltage rise/fall, data acquisition and calculation, and prints test results. One‑sequence‑parameter measurement takes around one minute; 5‑minute test workflow replaces traditional 2‑hour manual work.
6. High‑precision measurement. Built‑in near‑power‑frequency heterofrequency power source (47.5Hz & 52.5Hz) effectively separates field interference for high‑accuracy small‑signal measurement.
7. Solves existing drawbacks of conventional test equipment such as complicated wiring, poor anti‑interference performance, insufficient stability and low accuracy.
8. Stores up to 2048 groups of test data. Data can be exported to upper‑computer via USB port for data management and report generation.

Specifications

Item	Parameters
Power Supply	Three‑phase AC380V±10%, 15A, 50Hz (RMS)
Max Output Voltage	Three‑phase, 0‑200V(RMS,＜±1%)
Max Output Current	5A
Internal Heterofrequency Power‑Source Characteristics
Output Frequency	47.5Hz, 52.5Hz (＜±0.1Hz)
Active Power	Power factor:0.1‑1.0, ±0.5% reading ±1 digit47.5Hz, 52.5Hz (＜±0.1Hz)
Max Output Power	Three‑phase 3×3kW (9kW)
Measurable Object	Two‑phase lines, including HVDC transmission lines and electrified railway traction lines
Measuring Range
Capacitance	0.1‑30 μF
Impedance	0.1‑400 Ω
Impedance Angle	0°‑360°
Applicable Line Length	0.3km‑400km for stable measurement
Measurement Resolution
Capacitance	0.01 μF
Impedance	0.01 Ω
Impedance Angle	0.01°
Measurement Accuracy
Capacitance	≥1 μF: ±1% reading ±0.01 μF＜1 μF: ±3% reading ±0.01 μF
Impedance	≥1 Ω: ±1% reading ±0.01 Ω＜1 Ω: ±3% reading ±0.01 ΩTest condition: Current＞0.1A
Impedance Angle	±0.3°(Voltage＞1.0V), ±0.5°(0.2V‑1.0V)
Protection Functions	Over‑current, over‑voltage and earthing protection. Three‑phase fuses fitted on panel. Protect instrument and operators under proper high‑voltage test operation with reliable earthing connection. No instrument burnout risk.
Waveform Distortion Rate	Sine wave, distortion rate＜2%
Insulation & Vibration Resistance	Insulation ResistancePower input terminal:＞10 MΩCurrent output terminal:＞10 MΩVoltage measuring terminal:＞10 MΩ
Withstand Voltage	1.5kV, 1min, no flash‑over. Passes 0.5m drop test for field transportation and lab test.
Anti‑interference Parameter	Anti‑interference current: ≥50A when line terminals are short‑circuited and earthed. Accurate measurement under signal‑to‑interference ratio 1:10. Supports two‑phase line power‑frequency parameter test.
Weight	Main unit: 65kg
Operating Environment	‑15℃ ~ 40℃; Relative Humidity ≤90%
Overall Dimension	550×440×585 mm
Weight	61kg

FAQ‑Transmission Line Parameter Analyzer

Q1: What is the Transmission Line Parameter Analyzer used for?

A: It adopts heterofrequency testing principle to measure positive‑sequence / zero‑sequence capacitance, impedance, impedance angle, mutual inductance and coupling capacitance of overhead transmission lines, applicable for transmission lines and railway traction lines.

Q2: What line length does this device support?

A: It performs stable measurement for lines ranging from 0.3 km to 400 km, covering most overhead transmission‑line field‑test scenarios.

Q3: What is the core advantage of heterofrequency 47.5Hz / 52.5Hz power source?

A: The near‑power‑frequency heterofrequency signal effectively separates on‑site power‑frequency interference. It can complete accurate measurement even when the ratio of test signal to interference signal is 1:10.

Q4: Is complicated field wiring required for measurement?

A: No. Only one‑time connection to the down‑lead wires of the tested line is needed to finish all parameter tests, greatly simplifying on‑site work.

Q5: How long does one complete measurement take?

A: Single‑group sequence‑parameter measurement takes approximately 1 minute. The whole test procedure can be finished within 5 minutes, far faster than traditional manual test methods.

Q6: What data‑storage and export functions are available?

A: It can store up to 2048 groups of test data. Test records can be exported via USB interface to upper‑computer for data management and automatic report generation.

Q7: What are the measuring range and resolution for main parameters?

A: Capacitance: 0.1~30 μF, resolution 0.01 μF; Impedance:0.1~400 Ω, resolution 0.01 Ω; Impedance angle:0°~360°, resolution 0.01°.

Q8: What power supply does the analyzer require?

A: Three‑phase AC 380V±10%, 15A, 50Hz. Max three‑phase output power reaches 9 kW.

Q9: Does it support HVDC lines and electrified railway traction lines?

A: Yes. It supports parameter testing for two‑phase lines, including HVDC transmission lines and electrified railway traction lines.

Q10: What built‑in protection functions are equipped?

A: Built‑in over‑current, over‑voltage and earthing protection with three‑phase fuses. Reliable earthing of equipment ground terminal protects both instrument and operators.