ST-991 is mainly upgrade the hardware and software of the 980 model that is not anti-interference during testing. The anti-interference channel adopts a high anti-interference design, and the received signal will not be interfered under high-voltage lines, next to transformers and in cable trench environments.

The latest version adds the selection and switching function of standard signals and enhanced signals, and selects the appropriate working mode according to the strength of the on-site magnetic field, which can locate the fault point more quickly and accurately (domestic first, patent protection)

Applicable to the maintenance of street lamp cables, fault detection and repair of farmland irrigation cables, underground armored iron power cables in residential properties and garden green belts, outdoor power cables, highways, factories and mines, and tower communication base station direct buried power supply cable fault detection and other industries.

Features

1. Integrated digital multimeter (voltage, loop resistance, insulation resistance) test function, convenient for finding the fault lines and determining the fault type.

2. With length test function: supports testing cable line breakage, short-circuit fault distance, and can also test the total length of the cable.

3. With leakage detection function: for poor insulation caused by the destruction of the insulation layer of the buried line, to locate the ground leakage fault.

4. With path finding function: can easily find the exact direction of the buried cable.

5. With manual test function: supports manual setting interface, can manually select range, gain, wave speed and other test parameters.

6. With waveform comparison function: simultaneously display fault waveform and normal waveform, clearly and intuitively locate the fault location.

7. Signal generator has large screen displaying the waveform parameters. The parameters that can be set include signal amplitude (1-99), signal frequency (500-2000Hz), signal type (sine wave, square wave, audio, etc.) and transmission mode (continuous and intermittent), with one-key entry into energy-saving state function.

The anti-interference channel adopts a high anti-interference design. The signals under high-voltage lines and in cable trench environments will not be interfered.

Technical parameters

Few common Questions

Q: Is the tester you used under high-voltage lines, cable trenches, or anywhere else with live cables seriously interfering with the signal and making it hard to hear clearly?

A: The ST-991 cable fault locator adopts a high-filter anti-interference design. It will not be interfered with in complex electromagnetic environments. The signal is intuitive, and the sensitivity is adjustable and the positioning is accurate.

The ST-991 signal generator has multimeter function built in. It is convenient to test the line voltage, insulation between lines, insulation to ground, insulation between wire armors, and intuitively judge whether the line is completely short-circuited. It is more convenient to locate the fault location.

Q: When you use a leakage detector to test an underground iron cable, and the outer armor is good but the inner core wire is broken. Do you feel helpless because the detected signal is shielded by the outer armor?

A: The length test function of the ST-991 cable fault locator can easily test the length of the broken wire and short circuit and quickly locate the fault point

Q: Is your underground cable detector unable to judge the fault waveform then could not decide the fault location during the length test?

A: The ST-991 cable fault locator can display two waveform at the same time when testing the length. By comparing the good line waveform and the fault line waveform, it is easy to determine the fault waveform and accurately locate the fault position.

Q: What is the difference between ST-991 and ST-980 and those 980s sold online?

A: ST-991 is mainly updated the hardware and software based on ST-980 models which are not anti-interference during testing. The original 980 is under high-voltage lines or in cable trenches, and other cables are not powered off, and the headphones hear all noise. But 991 adopts a high anti-interference design. The received signal will not be interfered under high-voltage lines, next to transformers, and in cable trench environments, which greatly increases the scope of application.

Q: Can your ST-991 cable fault locator test armored iron cables?

A: Both armored iron cables and ordinary cables can be tested

Q: What voltage cables can your ST-991 cable fault tester test?

A: It can test various types of cables from hundreds of volts to less than 10KV

Q: What faults can your ST-991 cable fault tester test?

A: Cable disconnection, short circuit, ground leakage (insulation resistance within 0.5 megohms), and the path direction of underground cables can all be tested

Q: How many meters can be tested for underground cable?

A: The test depth is related to the type of fault. For line grounding faults, the smaller the grounding resistance, the bigger the current passing through the cable, the stronger the excited magnetic field, and the deeper the test depth. For the case of dead grounding at the fault point (the grounding resistance is generally around 2-4K measured by a multimeter), the test depth is more than 3 meters by adjusting the amplitude of the transmitter and the sensitivity of the receiver. On the contrary, when the grounding resistance is large, the magnetic field will weaken and the measured depth will be shallower. In addition, according to the on-site conditions, the probe or probe method can be appropriately selected to increase the signal acquisition range.

(During the test, the grounding wire of the signal generator must be well prepared. The principle is to directly insert it into the wet soil to ensure reliable grounding. Do not clamp the original grounding bar, doors and windows or grounding grid. It will affect the strength of the signal)