GE 850 User Manual

5–70 850 FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL
SYSTEM CHAPTER 5: DEVICE, SYSTEM, INPUT AND OUTPUT SETPOINTS
Breakers
Breaker detection ON is performed on the 850 relay by monitoring the state/states of
either one, or preferably two, contact inputs. It is highly recommended to monitor the
status of the feeder breaker using both breaker auxiliary contacts 52a, and 52b. However
using only one of them is also acceptable. The 850-E
and 850-D single feeder relays have
one controllable breaker. The 850-D dual feeder and 850-P relays have two controllable
breakers.
The breaker connection/disconnection to/from the power system (racked-out by the
breaker racking mechanism, or isolated by the associated disconnect switches on a fixed
circuit breaker) is provided by monitoring the contact input “BKR CONNECTED”. If the
contact input selected under the “BKR CONNECTED” setpoint is asserted, the breaker is
considered connected to the primary system. When the breaker is determined
disconnected, the breaker state is shown to be neither open, nor closed.
Path: Setpoints > System > Breakers > Breaker X
NAME
Range: Up to 13 alphanumeric characters
Default: BKR1
CONTACT INPUT 52a
Range: Off, Any FlexLogic operand
Default: Off
Selects the Contact Input connected to the breaker auxiliary contact 52a.
CONTACT INPUT 52b
Range: Off, Any FlexLogic operand
Default: Off
Selects the Contact Input connected to the breaker auxiliary contact 52b.
CONNECTED
Range: Off, Any FlexLogic operand
Default: Off
Select a contact input to show whether the breaker is connected (Racked-in, or
disconnect switches switched-on), or disconnected (racked-out, or disconnect switches
switched-off) from the system.
CLOSE RELAY SELECT
Range: Off, Relay 2
Default: Relay 2
FAST PATH:
If “Relay 2” is selected, Auxiliary Relay 2 is not available for selection in any element.
Table 5-9: Breaker status depending on availability of contacts 52a and 52b
52a Contact Configured 52b Contact Configured Breaker Status
Open Closed
Yes Yes 52a contact open
52b contact closed
52a contact closed
52b contact open
Yes No 52a contact open 52a contact closed
No Yes 52b contact closed 52b contact open
No No Breaker Not Configured

GE 850 Specifications

General

Brand	GE
Model	850
Category	Protection Device
Language	English

Summary

850 Feeder Protection System

Front Control Panel Interface

Common Setpoints

Provides a general description of common setpoints and their operational characteristics.

Device

Covers device configuration modes (Simplified/Regular) and custom configuration options.

Current Elements

Details various current-based protection elements like TOC, IOC, and directional overcurrent.

Trip and Close Circuit Monitoring

Local Control Mode (breakers and switches)

Details local control operations for breakers and switches via front panel or contact inputs.

FlexLogic

Explains the arrangement of internal digital logic and user-programmed parameters for flexible control.

Specifications

Provides detailed technical specifications for the device, including protection, input/output, and communication parameters.

Software Interface

Voltage Elements

Introduces undervoltage, overvoltage, and frequency protection elements.

Breaker Health

Breaker Failure (50BF)

Details the Breaker Failure scheme for detecting and responding to breaker failures.

Testing

Fault Reports

Cautions and Warnings

Outlines safety indicators, general precautions, and specific warnings for installation and operation.

Working with Setpoints & Setpoints Files

Security

Explains Basic Security and CyberSentry features, including roles, password complexity, and AAA server authentication.

Autoreclose

Covers the Autoreclose scheme for automatic reclosing after faults.

Transient Ground Fault Detection