Monitoring Functions; Function Overview - Siemens 7SG11 Argus Manual

7SG11 Argus
Overcurrent Protection Relay
Description
The 7SG11 Argus range of overcurrent protection combines
the power and flexibility of microprocessor technology with
decades of experience in the field of overcurrent protection
and auto-reclose. A wide range of protection elements are
supplemented by advanced features such as control, metering,
data storage and fibre-optic based communications.

Function Overview

•
IDMTL phase overcurrent stage
•
3 DTL phase overcurrent stages
•
IDMTL earth-fault stage
• 3 DTL earth-fault stages
• 2 instantaneous and DTL SEF/REF stages with har-
monic rejection, available as an option
• Trip circuit supervision
• Circuit breaker failure protection
•
CT supervision (7SG111 &7SG112)
•
Single pole, three pole and four pole variants
•
True RMS measurement
•
Status inputs with independent pick-up and drop-off
timers and logic inversion reduce scheme engineering
•
Flexible supply voltage ranges
• Low AC/DC burden
• Eight independent settings groups
•
Self, hand reset contacts
•
Extensive fault, sequence of event and disturbance
recorder
•
Fibre optic interface or RS485 multi-drop electrical
bus
• Continuous self-supervision of operation and power
supply
Siemens Protection Devices Limited

Monitoring Functions

Analogue values can be displayed in primary or secondary
quantities on the LCD screen. In addition the values can be
obtained via the communications port.
• Primary current per phase
•
Primary earth current
•
Secondary current per phase
•
Secondary earth current
• Primary phase voltages*
• Primary phase-phase voltages*
•
Secondary voltages*
•
Apparent power and power factor*
•
Real and reactive power*
•
WHr forward and reverse*
• VarHr forward and reverse*
•
Rolling and Max demand la, lb, lc
•
Rolling and Max demand W*
•
Rolling and Max Var*
•
Direction
• Autoreclose status
• Output contacts
•
Status inputs
•
Trip circuit healthy/failure
•
Trip counters
• I summation
2
• Number of waveform and event records stored
•
Time and Date
•
Starters
•
Power on counter
* 7SG1125 series models only
Data Storage and
Communication
Serial communications conform to IEC60870-5-103 or
Modbus RTU protocol. Up to 254 relays may be connected
in a ring network and addressed individually.
A fibre-optic communications port is provided on the rear of
the relay. It is optimised for 62.5/125μm glass fibre using
(BFOC/2.5) bayonet connectors. Optionally an RS485 electrical
connector can be provided.
Indication
LEDs for TRIP, STARTER and PROTECTION HEALTHY status.
7SG1144 and 7SG1164 relays also have LEDs indicating
CB OPEN and CB CLOSED status.
LCD – Alpha-numeric display for settings, instruments
and fault data.
ST
®
2