In some texts, the interquartile range is defined differently. It is defined as the difference between the largest and smallest values in the middle 50% of a set of data. To compute an interquartile range using this definition, first remove observations from the lower quartile.
A relay is an electrically operated switch. Many relays use an electromagnet to mechanically operate a switch, but other operating principles are also used, such as solid-state relays. Relays are used where it is necessary to control a circuit by a separate low-power signal, or where several circuits must be controlled by one signal.
Table 1 .- Criteria to determine possible alteration of the test period for relays Relay System Variables Factor Reducing Test Interval Factors lengthening Test Interval Type of Relays Complex (distance, differential), Simple (hinged armature plunger).. Time-Delay Starting or Closing Relay is a device that functions to give a desired amount of time delay before or after any point of operation in a switching sequence or protective relay system, except as specifically provided by device functions 48, 62, and 79.