The instrument adopts the method of "traveling wave test + comprehensive diagnosis of multiple electrical parameters", which can directly measure the cable length, the DC resistance of the conductor, the ambient temperature, etc., and then calculate the DC resistance per unit length of the conductor and the effective cross-sectional area of the conductor, etc.

Product Features
The multi-parameter tester for coiled cables, in combination with the measurement of multiple electrical parameters, can quickly measure and calculate the resistance per unit length of the cable conductor, the effective cross-sectional area of the conductor, the cable length, etc., providing an effective and accurate means for users to conduct cable quality inspection.

System function
The instrument adopts the method of "traveling wave test + comprehensive diagnosis of multiple electrical parameters", which can directly measure the cable length, the DC resistance of the conductor, the ambient temperature, etc., and then calculate the DC resistance per unit length of the conductor and the effective cross-sectional area of the conductor, etc. The instrument is equipped with two measurement modes: local measurement (hereinafter referred to as "local") and wireless remote measurement (hereinafter referred to as "remote"). The main unit of the instrument is equipped with a wireless Bluetooth module inside, which can stably and effectively communicate data with the remote terminal computer within a certain distance, flexibly responding to complex on-site environments. It is equipped with an internal integrated lithium battery charge and discharge management system, overvoltage and overcurrent protection system for charge and discharge, and an internal over-temperature protection system for the instrument.
 
Measuring the length of conductors by traveling waves: By injecting a low-voltage pulse signal into one end of the cable, the pulse signal propagates to the other end at a certain speed V. Due to impedance mismatch, the pulse is reflected. The pulse propagation time Δ t can be obtained through a high-speed counter, and the length L of the test cable can be calculated by the formula (it is not recommended to use this method for measurement when the cable length is less than 30 meters or more than 50 kilometers).
 
Measure the DC resistance of the conductor: The DC resistance of the cable conductor is measured through a precision resistance testing module. The resistance per unit length is calculated based on the cable length indicated by the manufacturer (or the actual measured cable length).
 
The instrument also has the function of calculating the length of the conductor by comparing the resistance value of the long conductor with that of the cut conductor, and also has the function of calculating the cross-sectional area of the conductor by comparing the length of the cable with the measured resistance value.
 
Technical index
The resistance of the cable is measured by a precision DC resistance measurement module. The measurement range is 0Ω to 100Ω, with a basic accuracy of ±0.2%+1uΩ. Temperature correction is automatically performed when calculating the resistance per unit length.

The length measurement adopts a high-precision pulse time counting module. The length measurement range is 30m to 50km, and the accuracy is better than ±1%+0.5m.

Precision temperature and humidity measurement module, measurement accuracy: temperature ±1%, humidity ±2%;

The effective transmission distance of the Bluetooth module is 0 to 30 meters in an open environment.

The lithium battery is 12.6V 15000mAh, a large-capacity battery pack. When fully charged, it can power the tester to stand by for more than 20 hours and actually run continuously for measurement for more than 8 hours.
 
Relevant implementation standards
GB/T 3956-2008 Conductors of cables
GB/T 6587-2012 General Specification for Electronic Measuring Instruments
GB/T 12604.1-2020 Non-destructive Testing Terminology - Ultrasonic Testing
GB/T 11344-2021 Non-destructive Testing - Ultrasonic Thickness measurement
JB/T 9329-1999 Basic Environmental Conditions and Test Methods for the Transportation and Storage of Instruments and Meters