Firmware Compliance; Operating Safety; Protection Functions - Allen-Bradley 857 Quick Start Manual

Chapter 1 Overview

Operating Safety

8

Firmware Compliance

The Settings files between major revisions of firmware are not compatible with
other major versions. This statement is true of products with version 10.xxx
firmware, version 12.xxx firmware, or higher.
IMPORTANT Do not load Settings file between relays of different version numbers.
ATTENTION: The terminals on the rear panel of the relay can carry
dangerous voltages, even if the auxiliary voltage is switched off. Do not place
a live current transformer secondary-circuit in an open circuit condition. The
disconnection of a live circuit can cause dangerous voltages! Any operational
measures must be conducted according to national and local directives and
instructions.
IMPORTANT Read the operation instructions before performing any operational
measures.

Protection Functions

The comprehensive protection functions of the relay
utility, industrial, marine, and offshore power distribution applications.
Because the 857 Protection System is designed for global applications, it
includes both ANSI IEEE and IEC protective function numbers and
symbology.
Table 1 - List of Protection Functions
IEEE/ ANSI Code IEC Symbol
25 df/dv
27 U<
U<<
U<<<
32 P<
P<<
37 I<
46R I >
2
46 I >
2
47 I >>
2
Rockwell Automation Publication 857-QS001B-EN-P - April 2017
Function Name
Synchrocheck
Undervoltage protection
Reverse power protection
Undercurrent protection
Current unbalance protection - Feeder protective
mode
Current unbalance protection - Motor protective
mode
Phase reversal / incorrect phase sequence protection Only available when
(Table 1) make it ideal for
Note
Only available when
application mode is
feeder protection.
Only available when
application mode is
motor protection.
application mode is
motor protection.