4. Basic relay measurement functions
It should be remembered that protection equipment is a measuring system that continuously monitors important network parameters (voltage, current or a combination of these). If at least one of the monitored measurement quantities exceeds a preset threshold value, or moves outside a measurement range considered normal (crossing a characteristic), the equipment initiates one or more actions, such as :
an additional measurement ;
starting a timer ;
sending a signal or a trip command to a circuit breaker.
All these actions are coordinated by the equipment's logic function.
Most protective equipment consists of several elementary measuring functions, often referred to as measuring relays. These must measure correctly...
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Basic relay measurement functions
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Bibliography
Events
CIGRE (Conseil International des Grands Réseaux Électriques): one of the world's leading organizations in the field of high-voltage electricity. It covers technical, economic, environmental, organizational and regulatory aspects. The Biennial Conference, held every even-numbered year in Paris (end of August), attracts some 3,000 delegates from 5 continents. Some 400 reports on all CIGRE themes are discussed.
Standards and norms
- Vocabulaire électrotechnique International. Chapitre 448. Protection des réseaux d'énergie - CEI 60050-448 -
- Relais électriques - CEI 60255 -
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