Heat Cycling Test Setup For Lugs

The CKINSTO Heat Cycling Test Setup for Lugs is a specialized system used to evaluate the long-term durability, stability, and integrity of electrical connections, specifically cable lugs, terminals, and connectors, under repeated thermal stress. This test is crucial for verifying that the connection maintains low electrical resistance over its operational lifetime, preventing catastrophic failure or fire hazards due to overheating. This test is often referred to as a Thermal Cycling Test or Temperature Cycling Test. Key Purpose and Standard Compliance Objective: To simulate the repeated heating and cooling cycles that electrical connections experience in service due to changes in electrical load (current) and ambient temperature. This exposes the connection to stresses caused by the differential thermal expansion and contraction between the conductor (cable) and the terminal material (lug). Failure Mechanism: Failure is typically indicated by an increase in contact resistance at the crimp or joint, leading to excessive heat generation, material degradation, and ultimately, system failure. Standards: The system is typically designed to comply with thermal cycling requirements in major industry standards, such as: IEC 61238-1: Compression and mechanical connectors for power cables. UL 486A-B: Standard for Wire Connectors and Soldering Lugs. IEEE 837: Standard for Qualifying Permanent Connections Used in Substation Grounding. 1. Current Injection and Cycling Unit High-Current Source: A powerful, regulated AC or DC current source (often a current transformer/injector) capable of delivering the required heating current. Capacity: Ranges from hundreds to thousands of amperes , depending on the size of the lugs being tested. Automated Cycling: A programmable switchgear system to automatically turn the current ON and OFF according to the test protocol's specified heating and cooling periods. 2. Test Chamber and Fixturing Test Bench/Busbars: Robust, high-conductivity copper busbars are used to connect the lugs and cables, minimizing the busbar's own heating. Reference Conductor: The standard requires one or more reference conductors of the same material and size as the cable under test to be included. The temperature rise of the lug connection is measured relative to this reference conductor. Fixtures: Specialized clamping and mounting fixtures ensure the lugs and cables are secured without adding extraneous mechanical stress. 3. Measurement and Control System Temperature Measurement: High-accuracy, multi-channel temperature monitoring using K-type Thermocouples or non-contact Infrared Cameras. Thermocouples are attached to the lug/connector and the reference conductor. Voltage Drop Measurement: High-precision instruments are used to measure the voltage drop across the crimp joint. This drop is directly related to the contact resistance . Control System: PLC-based control with a PC interface (SCADA) for fully automated operation.It allows the operator to set: Data Logging: Automatically records temperature rise, voltage drop, and cycle count for continuous monitoring and final reporting.