Siemens 7SR21 Manual page 17

Relay Information
Above the LCD three labels are provided, these provide the following information:
1) Product name and order code.
2) Nominal current rating, rated frequency, voltage rating, auxiliary dc supply rating, binary input supply
rating, configuration and serial number.
3) Blank label for user defined information.
A 'template' is available to allow users to create and print customised labels.
Liquid Crystal Display (LCD)
A 4 line by 20-character liquid crystal display indicates settings, instrumentation, fault data and control
commands.
To conserve power the display backlighting is extinguished when no buttons are pressed for a user defined
period. A setting within the "SYSTEM CONFIG" menu allows the timeout to be adjusted from 1 to 60 minutes and
"Off" (backlight permanently on). After an hour the display is completely de-activated. Pressing any key will re-
activate the display.
The LCD contrast can be adjusted using a flat blade screwdriver to turn the screw located below the contrast
symbol . Turning the screw clockwise increases the contrast, anti-clockwise reduces the contrast.
User defined indentifying text can be programmed into the relay using the System config/Relay Identifier
setting. The 'Relay Identifier' text is displayed on the LCD display at the top level of the menu structure and is
used in communication with Reydisp to identify the relay. Pressing the Cancel button several times will always
return the user to this screen.
'PROTECTION HEALTHY' LED
This green LED is steadily illuminated to indicate that DC voltage has been applied to the relay power supply and
that the relay is operating correctly. If the internal relay watchdog detects an internal fault then this LED will
continuously flash.
'PICKUP' LED
This yellow LED is illuminated to indicate that a user selectable function(s) has picked up. The LED will self reset
after the initiating condition has been removed. The same LED can be assigned two different colours dependent
upon whether a Pickup or Operate condition exists.
Functions are assigned to the PICKUP LED in the OUTPUT CONFIG>PICKUP CONFIG menu.
'TRIP' LED
This red LED is steadily illuminated to indicate that a user selectable function has operated to trip the circuit
breaker. Functions are assigned to the 'Trip' LED using the OUTPUT CONFIG>Trip Contacts setting.
Operation of the LED is latched and 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).
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.
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).
©2010 Siemens Protection Devices Limited
7SR21 & 7SR22 Argus Description of Operation
Chapter 1 Page 17 of 71