Bender technology is a complex subject, often difficult to understand. Here we explain the basic Bender know-how, displaying graphics and examples to better convey what our products achieve. In the below pages we explain ungrounded, grounded, HRG (high resistance grounding), offline monitoring, and monitoring and analysis with POWERSCOUT®.
If analyzing electrical installations, one frequently runs across the terms ground, grounded, and grounding. As the name suggests, a grounded system is one that has at least one conductor or point intentionally connected with the ground (or earth). Bender manufactures ground-fault products to monitor grounded systems for fault or residual currents. The sum of all conductors except the protective earth conductor is measured by means of measuring current transformers.
In general, ground-fault monitors (RCM - residual current monitors) are used to send a message to the user even before reaching the shutdown threshold of the GFCI. Ground-fault monitors detect deteriorations of the insulation level at an early stage and in a reliable way.
An ungrounded system is a system lacking intentional connection to the ground, except through measuring devices. Early detection of ground faults on ungrounded systems allows critical systems to remain online while faults are identified and resolved. By continuously monitoring the system's insulation resistance, Bender's ground-fault detectors can provide an early indication of both immediate and trending ground faults before leakage current may be of concern.
A high resistance grounding (HRG) system is when the neutral point of an electrical system is connected to ground through a current limiting resistor, detecting ground faults when they occur. High Resistance Grounding (HRG) systems are often used on industrial and critical power applications to maintain system uptime during a first ground fault. HRG systems are also used in tripping applications to help control touch potential on portable loads and improve personnel safety.