What is a current overload?
It can be in the form of an overload or short circuit. When applied to motor circuits an overload is any current, flowing within the normal circuit path, that is higher than the motor's normal Full Load Amps (FLA). A short-circuit is an overcurrent which greatly exceeds the normal full load current of the circuit.
2.0 Overcurrent protection devices: Protection against temperature is termed “overcurrent protection.” Overcurrents are caused by equipment overloads, by short circuits or by ground faults. Many circuit breakers are also known as molded case breakers or MCBs.
- An overloaded circuit. The power needed by the outdoor lights added to the load from the refrigerator, the heater and any other devices connected to the same circuit, and all of them running at once exceeded the capacity of the electrical wiring (Fig. In most cases, the device will be a circuit breaker that trips open.
- OCPDs protect circuits and equipment, but they protect circuits in one way and equipment in another. An OCPD protects a circuit by opening when current reaches a value that would cause an excessive temperature rise in the conductors.
- A ground fault is an inadvertent contact between an energized conductor and ground or equipment frame. The return path of the fault current is through the grounding system and any personnel or equipment that becomes part of that system. Ground faults are frequently the result of insulation breakdown.
Updated: 2nd October 2019