CHAPTER 7: PROTECTION
Single-pole operation
NOTE:
Trip output settings
PLUS
D90
LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL
This element must be used in single-pole operation applications.
The trip output element performs the following applications for single-pole operations:
•
Determines if a single-pole operation is performed
•
Collects inputs to initiate three-pole tripping, the autorecloser, and breaker failure
elements
•
Collects inputs to initiate single-pole tripping, the autorecloser, and breaker failure
elements
•
Assigns a higher priority to pilot-aided scheme outputs than to exclusively local inputs
The trip output element works in association with the following D90
•
Autoreclose
•
Breaker control
•
Open pole detector
•
Phase selector
These elements must be programmed and in-service for successful operation of the trip
output. The autorecloser must also be in the reset state before a single-pole trip can be
issued. Outputs from this element are also directly connected as initiate signals to the
breaker failure elements.
At least one internal protection element or digital input representing detection of a fault
must be available as an input to this element. In pilot-aided scheme applications, a timer
can be used to delay the output decision until data from a remote terminal is received from
communications facilities. This prevents a three-pole operation when a single-pole
operation is permitted.
Select the Settings > Protection > Control > Trip Output menu to access the trip output
settings.
CONTROL ELEMENTS
Plus
elements:
325