When a short circuit occurs in a circuit with loose conduit couplings and connectors, how is the opening time of an OCPD affected?

In the context of short circuits, the operation of overcurrent protective devices (OCPDs) is primarily determined by the magnitude of the current flowing through them rather than the physical condition of the conduit couplings and connectors. When a short circuit occurs, the fault current generally rises very quickly to levels far exceeding the normal operating current, triggering the OCPD to open the circuit.

Loose conduit couplings and connectors can lead to increased resistance at those junctions, which might cause arcing or intermittent connections. However, this increase in resistance does not fundamentally change the operational principle of the OCPD in relation to short circuits. The device is designed to respond to overcurrent conditions, and its opening time is based on detecting those high currents.

Thus, while loose fittings may introduce other electrical issues over time, they do not directly influence the immediate performance of the OCPD during a short circuit, particularly when considering the massive surges of current involved. Hence, the opening time of the OCPD remains unaffected in terms of its response to short circuit conditions.