Short circuit loop impedance measurement

As an electrical wholesaler, we offer a wide range of modern measuring devices. Our assortment includes various types of meters and multimeters and accessories for them. In this category, you will find short-circuit loop meters with a wide voltage range. These devices are commonly used by electrical installers and measuring engineers as well as electrical maintenance services. See available products and order a short-circuit loop impedance meter with the required parameters.

What is fault loop impedance measurement?

Every electrical installation must be equipped with effective protection against electric shock. This is required by law. The basic form of protection is the insulation of conductive parts, protecting against direct contact. However, as a result of damage or short circuit in the installation, there is a risk of contact with conductive parts of devices that are not under voltage under normal conditions. In such cases, additional protection should be activated - against indirect contact. It consists of various types of switches, which in the event of a failure are responsible for automatically switching off the power supply to the circuit, thus preventing electric shock to the user, damage to expensive equipment or the outbreak of fire. In order to check the effectiveness of this additional protection against electric shock, and consequently - the safety of the electrical installation and its users, a measurement of the short circuit loop impedance (ZS) is performed. The test is performed on a closed electrical system in which a short circuit occurs.

How to measure fault loop impedance?

To measure the short circuit loop impedance, you must:

• determine the tripping current (IA),
• calculate the allowable short circuit loop impedance using the formula,
• perform the measurement using a professional short circuit loop impedance meter.

Most often, a so-called artificial short circuit is induced. The meter will measure the voltage both without load and when loaded with a short circuit resistor.

Application of the short circuit loop impedance meter

The short circuit loop impedance meter provides information on the effectiveness of the power switch operation when a short circuit occurs in a given electrical system. This is a professional device designed for installers and measuring technicians providing their services in single-family and multi-family buildings, office buildings, industrial plants and other facilities equipped with low-voltage electrical installations. Measurements using the short circuit loop impedance meter are also performed by electrical maintenance services.

Fault loop impedance meters at the Onninen electrical wholesaler

We offer professional short circuit loop impedance meters with various parameters, from renowned manufacturers of measuring instruments, such as Sonel. The assortment includes both basic models - portable and handy, ideal for work at low nominal voltages, as well as advanced devices that allow for measurements in networks with high nominal voltage. When repeatedly measuring short circuit loop impedance, we recommend meters with an efficient ventilation system, ensuring a shortened cooling time of the short circuit resistor. Don't know which short circuit loop impedance meter to choose? Contact us! Onninen consultants will be happy to help.