Siemens SIMPRO-100 - Energy Metering Functionality; Power Measurement Conventions; IEEE Convention for Power Measurement

SIMPRO-100
Metering & Monitoring
8
PRIM-2400C 111
8 Metering & Monitoring
8.1 Introduction
The SIMPRO-100 Relay features metering
functions to display the present values of current
and (if included) voltage and RTD
measurements. The relay provides several
methods to read the present meter values,
including:
• Rotating front-panel display
• Front-panel menu
• EIA-232 serial port (using SIMPRO-PC or
ASCII text command)
• Rear-panel EIA-232 (using SIMPRO-PC or
ASCII text command) or EIA-485 port (using
Modbus
®
protocol)
• Analog output
Motor load monitoring and trending are possible
using the Load Profile function. The relay
automatically configures itself to save available
meter values every 15 minutes for 34 or 48 days.
For preventive maintenance purposes, the
SIMPRO-100 Relay provides a motor operating
statistics report, available using the front panel or
serial port.
Also helpful in preventive maintenance tasks, the
SIMPRO-100 Relay calculates and stores motor
starting information. The relay retains motor start
reports for the five latest motor starts. The motor
start trending function stores motor start
averages for the last eighteen 30-day periods.
8.1.1 Metering
SIMPRO-100 Relay meter data fall into several
categories:
• Instantaneous metering
• Demand metering
• Max/Min metering
• Thermal metering
• Energy metering
Details on each of the meter data types are
shown below. Chapter 5, page 75 and Chapter 6,
page 85 describe how to access the various
types of meter data using the relay front panel
and serial ports.
8.1.2 Instantaneous Metering
Table 8.1 Measured Values
The relay displays both the fundamental
frequency component and the RMS values of
several measurands. The fundamental frequency
signal has a defined magnitude and phase angle
with respect to the other quantities. Reported
Relay Option Meter Values
All Models Ia, Ib, Ic, In Fundamental Magnitudes
and Phase Angles; RMS Values
Ig Residual Current Fundamental
Magnitude and Phase Angle
Negative-Sequence Current (3I
2
)
Magnitude and Phase Angle
Frequency
% Unbalance
With Voltage Inputs Vab, Vbc, Vca Fundamental Magnitudes
and Phase Angles; RMS Values
Vg Residual Voltage Fundamental
Magnitude and Phase Angle
(wye-connection only)
Negative-Sequence Magnitude and
Phase Angle
kW Fundamental and RMS Values
HP, kVAR, kVA, and pf