SUMMARY OF IEEE GUIDE FOR THE PROTECTION OF NETWORK TRANSFORMERS

The “Summary Paper for the IEEE Guide for the Protection of Network Transformers” has been written to publicize the existence of C37.108-198X, a new IEEE Guide. It describes the equipment used in a typical network transformer system. The performance of this equipment is described during fault and non-fault system conditions. The limitations of the present protection are addressed, most importantly, for low-voltage, low-current arcing faults. Protective devices that can be added to the existing network transformer protection are listed. Some of these devices sense conventional input quantities such as phase current, ground current, impedance, and transformer rate-of-pressure rise, whereas others sense heat, ultraviolet light, and smoke. The application of interrupting devices such as circuit breakers, vacuum interrupters, fuses, and current limiting fuses including an electronic fuse are discussed with special application considerations stated. An example is included as an appendix to the guide which demonstrates how a protective system can be designed utilizing the devices described within the guide. © 1990 IEEE