An insulation tester is a specialized device used in cybersecurity and electrical engineering to measure the electrical resistance of insulating materials, such as cables, wires, and electronic components. By applying a high voltage across the insulation, the tester detects any leakage current, which could indicate degradation or failure of the insulation. This process helps ensure that electrical systems are protected from short circuits, electrical shocks, and other hazards. In cybersecurity, insulation testers can be used to assess the physical security of network infrastructure, preventing unauthorized access or tampering through compromised insulation. Regular testing improves safety and reliability in both industrial and IT environments.