This may involve reconfiguring the relay settings, adjusting pickup or time delay values, or replacing faulty hardware components. Motor protection relays protect against damage and downtime caused by problems such as overcurrent, phase loss, voltage unbalance and more. Unlike old-fashioned overload relays, modern relays are intelligent electronic devices that can tell the operator which condition triggered a shutdown. A current-limiting fuse can cut off the short-circuit current before it reaches damaging levels. Troubleshooting involves identifying and resolving issues that can arise in relay protection systems, such as faulty operation. Selective short-circuit protection can be achieved in different ways, such as: Time-graded protection Time- and current-graded protection A straightforward way of obtaining selective protection is to use time grading. The principle is to grade the operating times of the relays in such a way that.