FZY-3 Stray Current Tester: Technical Overview and Operational Guide

The FZY-3 Stray Current Tester is a specialized, rectifier-type instrument designed for the critical task of detecting and measuring stray electrical currents and voltages in underground mining environments. The presence of such stray energy—often induced on rails, water pipes, and cable sheaths—poses a severe safety risk, including the premature detonation of electric detonators or potential ignition of flammable atmospheres. This device serves as a frontline diagnostic tool for preventing such hazards.

Core Features and Advantages

The FZY-3 distinguishes itself through a combination of practicality, safety, and performance:

1.Dual-Mode Measurement: It can accurately measure both AC and DC stray voltage and current separately, providing a comprehensive picture of the electrical environment. This is crucial as stray currents can originate from various DC (e.g., trolley lines) and AC (e.g., power system leakage) sources.

2.Intrinsic Safety & Self-Sufficiency: The instrument requires no external power source for operation, enhancing its reliability and safety. This design eliminates potential ignition risks from internal batteries in hazardous areas and ensures the device is always ready for use.

3.Portability: Its compact size and lightweight construction make it an ideal tool for technicians who need to conduct surveys across extensive underground networks.

1Detailed Technical Specifications

The tester offers wide-ranging scales to accommodate varying field conditions:

1. Current Measurement:

Ranges: 0 - 50 mA - 250 mA - 1 A - 5 A - 10 A

Accuracy (AC): ±5% of full scale.

Remark: A mandatory pre-use zero adjustment is required to ensure accuracy.

2. Voltage Measurement:

Ranges: 0 - 0.2 V - 1 V - 4 V - 20 V - 40 V

Accuracy (DC): ±2.5% of full scale.

Remark: As with current measurement, the meter hand must be zeroed before initiating voltage tests.

Operational Protocol and Best Practices

For technicians, adherence to correct procedure is paramount:

1.Pre-Use Zeroing: Before any measurement, the meter pointer must be mechanically set to zero. This is a critical step for maintaining the stated measurement accuracy across all ranges.

2.Range Selection: Begin with the highest applicable range when the expected magnitude is unknown, then step down to a lower range for a more precise reading, avoiding needle overdrive.

3.Application: The probes should be firmly connected to the conductive structure under test (e.g., rail, pipe). For current measurement, the device must be connected in series with the path of the stray current. For voltage measurement, it is connected in parallel across the points of interest.

4.Interpretation: Readings should be documented alongside the measurement location and associated infrastructure. Trends or values approaching hazardous thresholds (as defined by mine safety standards) must be reported immediately for corrective action, such as improving rail bonding or isolating ground paths.

Conclusion

The FZY-3 Stray Current Tester is an essential, no-frills instrument for maintaining electrical safety in underground coal mines. Its robust design, wide measurement bands, and simple operation make it a reliable choice for monitoring the invisible threat of stray currents. By enabling regular and accurate surveys, it empowers safety and electrical technicians to identify and mitigate risks proactively, forming a key component of a comprehensive mine safety program.

GDZX is a manufacturer of power detection equipment, offering a diverse range of products with comprehensive models and providing professional technical support. Contact us at +86-27-6552607 or +86-17396104357.Website: http://en.gdzxdl.com/