short circuit under load

In a power supply circuit, this refers to short-circuiting the output terminals with a jumper wire or similar low-resistance conductor. In that case, it constitutes a short circuit including the contact resistance of the output terminals and the wiring impedance such as the jumper wire. Load short circuits are electrical accidents caused by moisture intrusion due to humidity or insulation deterioration over time. When a load short circuit occurs, not only can the power supply circuit fail due to heat generated by excessive short-circuit current, but there is also a risk of electrical fires from heating or arc discharge. Therefore, many power supply circuits are equipped with safety devices that detect load short circuits and reduce or stop the output current. In some cases, a load short circuit may be performed as an operation test of the safety device during factory inspection of the power supply circuit.