CHAPTER 5: SETTINGS PRODUCT SETUPB30 BUS DIFFERENTIAL SYSTEM – INSTRUCTION MANUAL 5-1195Figure 5-50: Thermal demand characteristic5.3.11.2 Calculation method 2: Block intervalThis method calculates a linear average of the quantity (RMS current, real power, reactive power, or apparent power) overthe programmed demand time interval, starting daily at 00:00:00 (that is, 12:00 am). The 1440 minutes per day is dividedinto the number of blocks as set by the programmed time interval. Each new value of demand becomes available at theend of each time interval.5.3.11.3 Calculation method 2a: Block interval (with start demand interval logic trigger)This method calculates a linear average of the quantity (RMS current, real power, reactive power, or apparent power) overthe interval between successive Start Demand Interval logic input pulses. Each new value of demand becomes available atthe end of each pulse. Assign a FlexLogic operand to the DEMAND TRIGGER setting to program the input for the newdemand interval pulses.5.3.11.4 Calculation method 3: Rolling demandThis method calculates a linear average of the quantity (RMS current, real power, reactive power, or apparent power) overthe programmed demand time interval, in the same way as Block Interval. The value is updated every minute andindicates the demand over the time interval just preceding the time of update.5.3.12 User-programmable LEDs5.3.12.1 Menu - Enhanced and standard front panelsSETTINGS PRODUCT SETUP USER-PROGRAMMABLE LEDSIf no trigger is assigned in the DEMAND TRIGGER setting and the CRNT DEMAND METHOD is "Block Interval," usecalculation method 2. If a trigger is assigned, the maximum allowed time between two trigger signals is 60 minutes.If no trigger signal appears within 60 minutes, demand calculations are performed and available, and the algorithmresets and starts the new cycle of calculations. The minimum required time for trigger contact closure is 20 μs. USER-PROGRAMMABLE LEDS LED TESTSee below TRIP & ALARM LEDSSee page 5-122 USER-PROGRAMMABLE LED 1See page 5-122 USER-PROGRAMMABLE LED 48
