How is instantaneous overcurrent is set in CTMM relays?
Instantaneous overcurrent settings in Current Transformer (CT) Metering and Monitoring (CTMM) relays are typically established by configuring the relay's pickup current level and time delay characteristics. This involves adjusting the relay's settings to specify the threshold current at which the relay will trip, often measured as a multiple of the CT's rated primary current. The settings can be fine-tuned based on system requirements and fault analysis to ensure prompt response to overcurrent conditions while avoiding nuisance tripping. Additionally, some relays may offer features like curve selection to tailor the response to specific operational needs.