Current Inputs - Siemens 7SR23 DAD Manual

High impedance protection relay

Indication LEDs

Relays have either 8 or 16 user programmable LED indicators. Each LED can be programmed to be illuminated

as either green, yellow or red. Where an LED is programmed to be lit both red and green it will illuminate yellow.

Each LED can be assigned two different colours dependent upon whether a Start/Pickup or Operate condition

initiates operation. The LED illumination colour is assigned in the OUTPUT CONFIG>LED CONFIG menu for both

Pickup and Operate initiation.

Functions are assigned to the LEDs in the OUTPUT CONFIG>OUTPUT MATRIX menu.

Each LED can be labelled by withdrawing the relay and inserting a label strip into the pocket behind the front

fascia. A 'template' is available to allow users to create and print customised legends.

Each LED can be user programmed as hand or self–resetting. Hand reset LEDs can be reset by either pressing

the TEST/RESET

button, energising a suitably programmed binary input, or, by sending an appropriate

command over the data communications channel(s).

The status of hand reset LEDs is maintained by a back up storage capacitor in the event of an interruption to the

d.c. supply voltage.

Standard Keys

The relay is supplied as standard with five pushbuttons. The buttons are used to navigate the menu structure and

control relay functions. They are labelled:

TEST/RESET

ENTER

CANCEL.

NOTE: All settings and configuration of LEDs, BI, BO and function keys can be accessed and set by the user

using these keys. Alternatively configuration/settings files can be loaded into the relay using the 'ReyDisp'

programs.

2.6

Current Inputs

Four current inputs are provided on the Analogue Input module. Terminals are available for both 1A and 5A

inputs. CT ratios are input by the user in the CT CONFIG menu.

Analogue waveform processing is optimised to provide high security operation. Current is sampled at 1600Hz for

50Hz systems and 1920Hz for 60Hz systems (32 samples per cycle).

The waveform recorder samples and displays current input waveforms at 32 samples per cycle.

Increases a setting or moves up menu.

Decreases a setting or moves down menu.

Moves right, can be used to reset selected functionality and for LED test (at

relay identifier screen).

Used to initiate and accept settings changes.

Used to cancel settings changes and/or move up the menu structure by one

level per press.

Chapter 1) 7SR23 DAD Description Of Operation

Chapter 1 Page 12 of 36

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