Schneider Electric PM5100 Marine Instruments User Manual


 
PowerLogic™ PM5100 series user guide Chapter 8—Measurements and calculations
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8:00 am, select 0800 (in hhmm format). When setting up this type of demand, you
can choose Clock Sync Block (clock-synchronized block demand) or Clock Sync
Roll Blk (clock-synchronized rolling block demand). Clock Sync Roll Blk requires
that you specify a subinterval.
Thermal demand
Thermal demand calculates the demand based on a thermal response, which imitates
the function of thermal demand meters. The demand calculation updates at the end of
each interval. You can set the demand interval from 1 to 60 minutes (in 1-minute
increments).
The following illustration shows the thermal demand calculation. In this example, the
interval is set to 15 minutes.
Current demand
The power meter calculates current demand using one of the methods described in
“Power demand calculation methods” on page 63. You can set the demand interval
from 1 to 60 minutes in 1-minute increments (for example, 15 minutes).
Predicted demand
The power meter calculates predicted demand for the end of the present interval for
kW, kVAR, kVA and Amps demand. This prediction takes into account the energy
consumption so far within the present (partial) interval and the present rate of
consumption.
Predicted demand is updated every second.
The following illustration shows how a change in load can affect predicted demand for
the interval. In this example, the interval is set to 15 minutes.
Thermal demand example
The interval is a window of time that moves across the timeline
15-minute
interval
next
15-minute
interval
Time
(minutes)
Last completed
demand interval
Calculation updates at the end of each interval
% of Lead
0%
90%
99%