BE1-951
Reporting and Alarm Functions
6-7
RE-KVAR Command
Purpose:
Read, change, or reset the three-phase var-hours in primary units.
Syntax:
RE-KVAR[=<x>]
Comments:
x = 0 to 100,000 (values must be entered in kilovar-hours)
A maximum value of 100 Mvarh is reported.
1.
RE-KVAR Command Example
Obtain the current var-hour values.
>RE-KVAR
13.24MVARH, -7902.18KVARH
Energy data is also available through the communication ports by using the RE (report energy) command.
This read-only command returns both the watt-hours and var-hours.
RE Command
Purpose:
Report all energy data.
Syntax:
RE
RE Command Example
1.
Obtain the current watt-hour and var-hour values.
>RE
RE-KWH=24.01MWH, -2720.26KWH
RE-KVARH= 13.24MVARH, -7902.18KVARH
DEMAND FUNCTIONS
The demand reporting function continuously calculates demand values for the three-phase currents, three-
phase power, three-phase reactive power, neutral current(3-Phase Residual 3IO), and negative sequence
current. Demand values are recorded with time stamps for Peak Since Reset, Yesterday’s Peak, and
Today’s Peak. Programmable alarm points can be set to alarm if thresholds are exceeded for overload and
unbalanced loading conditions.
Demand Calculation and Reporting
An algorithm in the demand reporting function digitally simulates a thermal or exponential response.
Demand values are computed by an exponential algorithm with the demand interval or response period
defined as the time taken by the meter to reach 90 percent of the final value for a step change in the current
being measured. Demand interval can be set independently for the phase, neutral, and negative sequence
demand calculations. The reactive power and power demand intervals always match the phase demand
interval setting.
Each time that the value in the current demand register is updated, it is compared to the values stored in the
Peak Since Reset and the Today’s Peak registers. If the new demand is greater, the new value and time
stamp is entered into the appropriate registers. In addition, the demand reporting function keeps an
additional set of registers for Yesterday’s Peak. Each day at midnight, the demand reporting function
replaces the values and time stamps stored in yesterday’s peak registers with the values and time stamps
from today’s peak registers. It then starts recording new information in Today’s Peak registers. Demand
registers are stored in volatile memory.
Today’s Peak and Yesterday’s Peak registers are read only. Values in the Peak Since Reset registers can
be reset to zero or preset to a predetermined value. For example, if some loads will be switched to remove
a feeder from service and you don’t want the abnormal loading to affect the Peak Since Reset register
values, these values can be read prior to switching the loads. Once the abnormal loading condition has
passed, the registers can be reset to the original values.
