Siemens 7SR51 - 8.1 Introduction

Introduction
The measurands are recorded from the analogue inputs.
Further measurands are calculated from these measured values where the instrument or meter requires meas-
urands from more than 1 input. For example, the electric power is calculated from the voltage and current
measurands.
For the display, the measured values of a device are summed up in the following groups:
•
Operational measured values
•
Fundamental and symmetrical components
•
Function-specific measured values
•
Minimum values, maximum values, average values
•
Energy metered values
The device instrumentation and metering provides real-time measured quantities and data, this is displayed on
the relay fascia LCD (when in Instruments Mode) or via the data communications interface.
The primary values are calculated using the CT and VT parameters i.e. the values entered in the Configura-
tion > CT/VT menu – see section 3.3 CT and VT Inputs .
The user can add the meters that are most commonly viewed to a Favorites window by pressing the Enter
key when viewing a meter. The relay will display the favorite meters after elapse of the Configuration >
Device > Favorite Meters Timer setting. When more than 1 favorite meter is selected each selected
meter is displayed on the LCD for 5 seconds.
The energy storage meters can be reset from a binary input and have a user selectable setting for their meas-
urement in the Configuration > Data Storage menu. See section 3.6 Data Storage .
Counter instruments can be rest by pressing the ▶ key when the instrument is displayed.
8.1
Instruments and Meters
8.1 Introduction
442 Reyrolle 7SR5, Overcurrent Protection Device, Device Manual
C53000-G7040-C014-1, Edition 11.2019