CHAPTER 6: ACTUAL VALUES METERINGF60 FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL 6-216This menu displays metered values for current and power demand. The "SRC 1" text is replaced by the name programmedby the user for the associated source (see SETTINGS SYSTEM SETUP SIGNAL SOURCES).The relay measures (absolute values only) the source demand on each phase and average three phase demand for real,reactive, and apparent power. These parameters can be monitored to reduce supplier demand penalties or for statisticalmetering purposes. Demand calculations are based on the measurement type selected in the SETTINGS PRODUCT SETUP DEMAND menu. For each quantity, the relay displays the demand over the most recent demand time interval, themaximum demand since the last maximum demand reset, and the time and date stamp of this maximum demand value.Maximum demand quantities can be reset to zero with the CLEAR RECORDS CLEAR DEMAND RECORDS command.6.4.2.9 Frequency meteringACTUAL VALUES METERING SOURCE SRC 1 FREQUENCYThe metered frequency values are displayed in this menu. The "SRC 1" text is replaced by the name programmed by theuser for the associated source (see SETTINGS SYSTEM SETUP SIGNAL SOURCES).SOURCE FREQUENCY is measured via software-implemented zero-crossing detection of an AC signal. The signal is either aClarke transformation of three-phase voltages or currents, auxiliary voltage, or ground current as per source configuration(see the SYSTEM SETUP POWER SYSTEM settings). The signal used for frequency estimation is low-pass filtered. The finalfrequency measurement is passed through a validation filter that eliminates false readings due to signal distortions andtransients. SRC 1 DMD IB MAX:0.000 A SRC 1 DMD IB DATE:2001/07/31 16:30:07 SRC 1 DMD IC:0.000 A SRC 1 DMD IC MAX:0.000 A SRC 1 DMD IC DATE:2001/07/31 16:30:07 SRC 1 DMD W:0.000 W SRC 1 DMD W MAX:0.000 W SRC 1 DMD W DATE:2001/07/31 16:30:07 SRC 1 DMD VAR:0.000 var SRC 1 DMD VAR MAX:0.000 var SRC 1 DMD VAR DATE:2001/07/31 16:30:07 SRC 1 DMD VA:0.000 VA SRC 1 DMD VA MAX:0.000 VA SRC 1 DMD VA DATE:2001/07/31 16:30:07 FREQUENCY SRC 1 SRC 1 FREQUENCY:0.00 Hz