IEEE C37.2:1991 pdf download.IEEE Standard Electrical Power System Device Function Numbers.
IEEE C37.2 applies to the definition and application of function numbers for devices used in electrical substations and generating plants and in installations of power utilization and conversion apparatus.
1.2 References. This standard shall be used in conjunction with the following publications. When the following standards are superseded by an approved revision, the revision shall apply.
[1] ASME Y1.1-1989, Abbreviations for Use on Drawings and in Text.
[2] IEEE Std 315-1975, iEEE Standard Graphic Symbols for Electrical and Electronics Diagrams (ANSI).
[3] IEEE C37.1-1987, IEEE Standard Definition, Specification, and Analysis of Systems Used for Supervisory Control, Data Acquisition, and Automatic Control.
[4] IEEE C37.20.1-1987, IEEE Standard for Metal-Enclosed Low-Voltage Power Circuit Breaker Switchgear (ANSI).
[5] IEEE C37.20.2-1987, IEEE Standard for Metal-Clad and Station-Type Cubicle Switchgear (ANSI).
2. Purpose of Devi Funon Numbers
A device function number, with an appropriate prefix and suffix where necessary, is used to identify the function of each device in all types of partial-automatic and automatic switchgear and in many types of manual switchgear. These numbers are to be used in drawings, elementary and connection diagrams, instruction books, publications, and specifications. In addition, for automatic switchgear, the number may be placed on, or adjacent to, each device on the assembled equipment so that the device may be readily identified.
3. Standard Devi Fuztion Numbers
3.1 Standard Devi Function Numbers. Each number with its corresponding function name and the general description of each function is listed below.
1. master element. The initiating device, such as a control switch, etc., that serves, either directly or through such permissive devices as protective and time-delay relays, to place equipment in or out of operation.
2. time-delay starting or closing relay. 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.
3. checking or interlocking relay. A relay that operates in response to the position of a number of other devices (or to a number of predetermined conditions) in equipment to allow an operating sequence to proceed, stop, or provide a check of the position of these devices or conditions for any purpose.
4. master contactor. A device, generally controlled by device function 1 or the equivalent and the required permissive and protective devices, that serves to make and break the necessary control circuits to place equipment into operation under the desired conditions and to take it out of operation under abnormal conditions.
5. stopping device. A control device used primanly to shut down equipment and hold it out of operation.IEEE C37.2 pdf download.