Allen-Bradley 857 User manual

857 Protection System
For Feeder and Motor Protection
Bulletin 857, Series A
User Manual

Solid-state equipment has operational characteristics differing from those of electro-
mechanical equipment. Safety Guidelines for the Application, Installation and
Maintenance of Solid-State Controls (Publication SGI-1.1 available from your local
Rockwell Automation sales office or online at http://literature.rockwellautomation.com)
describes some important differences between solid-state equipment and hard-wired
electromechanical devices. Because of this difference, and also because of the wide variety of
uses for solid-state equipment, all persons responsible for applying this equipment must
satisfy themselves that each intended application of this equipment is acceptable.
In no event will Rockwell Automation, Inc. be responsible or liable for any indirect or
consequential damages resulting from the use or application of this equipment.
The examples and diagrams in this manual are included solely for illustrative purposes.
Because of the many variables and requirements associated with any particular installation,
Rockwell Automation, Inc. cannot assume responsibility or liability for actual use, based on
the examples and diagrams.
No patent liability is assumed by Rockwell Automation, Inc. with respect to use of
information, circuits, equipment, or software described in this manual.
Reproduction of the contents of this manual, in whole or in part, without written
permission of Rockwell Automation, Inc. is prohibited.
Throughout this manual, when necessary we use notes to make you aware of safety
considerations.
WARNINGWARNING
Identifies information about practices or circumstances that can
cause an explosion in a hazardous environment, which may lead
to personal injury or death, property damage, or economic loss.
IMPORTANTIMPORTANT
Identifies information that is critical for successful application
and understanding of the product.
ATTENTIONATTENTION
Identifies information about practices or circumstances that can
lead to personal injury or death, property damage, or economic
loss. Attentions help you identify a hazard, avoid a hazard, and
recognize the consequences.
SHOCK HAZ ARDSHOCK HAZ ARD
Labels may be on or inside the equipment (for example, drive or
motor) to alert people that dangerous voltage may be present.
BURN HAZARDBURN HAZARD
Labels may be on or inside the equipment (for example, drive or
motor) to alert people that surfaces may reach dangerous
temperatures.
Important User
Information

Table of Contents
857-UM001A-EN-P – July 2009
Chapter 1 Overview Introduction ............................................................................. 1-1
Main Relay Features ................................................................1-1
User Interface ...........................................................................1-4
Operating Safety ..................................................................... 1-4
Chapter 2 Relay Front Panel ....................................................................2-1
Display ............................................................................. 2-1
Menu Navigation and Pointers ......................................... 2-3
Keypad ............................................................................. 2-3
Operation Indicators ......................................................... 2-4
Resetting Latched Indicators and Output Relays ............. 2-5
Adjusting Display Contrast .............................................. 2-5
Local Panel Options ................................................................ 2-5
Navigating in Menus ........................................................ 2-5
Main Menu ....................................................................... 2-7
Menu Structure of Protection Functions .......................... 2-9
Setting Groups ................................................................ 2-12
Fault Logs ....................................................................... 2-13
Operating Levels ............................................................ 2-14
Opening Access .............................................................. 2-15
Password Handling ......................................................... 2-15
Operating Measures .............................................................. 2-16
Control Functions ........................................................... 2-16
Measured Data ............................................................... 2-17
Reading Event Register .................................................. 2-20
Forced Control (Force) ................................................... 2-20
Configuration and Parameter Setting .................................... 2-21
Parameter Setting ........................................................... 2-22
Setting Range Limits ...................................................... 2-23
Disturbance Recorder Menu DR .................................... 2-24
Configuring Digital Inputs DI ........................................ 2-25
Configuring Digital Outputs DO .................................... 2-25
Protection Menu Prot ..................................................... 2-25
Configuration Menu CONF ........................................... 2-26
Protocol Menu Bus ......................................................... 2-29
Single Line Diagram Editing .......................................... 2-33
SetPoints PC Software .......................................................... 2-34
Local Panel User
Interface

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Chapter 3 Protection Functions Maximum Number of Protection Stages ................................ 3-1
Protection Functions ............................................................... 3-1
General Features of Protection Stages .................................... 3-2
Setting Groups .................................................................. 3-2
Forcing Start or Trip Condition for Testing ..................... 3-2
Forcing Start or Trip Condition for Testing Purposes ...... 3-2
Start and Trip Signals ....................................................... 3-3
Output Matrix ................................................................... 3-3
Blocking ........................................................................... 3-3
Retardation Time .............................................................. 3-3
Reset Time (Release Time) .............................................. 3-4
Hysteresis or Dead Band .................................................. 3-5
Function Dependencies ........................................................... 3-5
Application Modes ........................................................... 3-5
Current Protection Function Dependencies ...................... 3-6
Overcurrent Stage I> (50/51) .................................................. 3-6
Three Independent Stages ................................................ 3-6
Inverse Operation Time .................................................... 3-6
Inverse Time Limitation ................................................... 3-7
Cold Load and Inrush Current Handling .......................... 3-7
Setting Groups .................................................................. 3-7
Recorded Values of the Latest Eight Faults ..................... 3-9
Directional Overcurrent Protection Idir> (67) ........................ 3-10
Four Independent Stages ................................................ 3-12
Inverse Operation Time .................................................. 3-12
Inverse Time Limitation ................................................. 3-12
Cold Load and Inrush Current Handling ........................ 3-12
Setting Groups ................................................................ 3-12
Recorded Values of the Latest Eight Faults ................... 3-15
Broken Line Protection I2/I1> (46R) ..................................... 3-15
Current Unbalance Protection I2> (46) ................................. 3-16
Inverse Delay ................................................................. 3-17
More Stages (Definite Time Delay only) ....................... 3-17
Setting Groups ................................................................ 3-17
Recorded Values of the Latest Eight Faults ................... 3-19
Incorrect Phase Sequence Protection I2>> (47) .................... 3-19
Stall Protection Ist> (48) ....................................................... 3-19
Frequent Start Protection N> (66) ........................................ 3-21
Undercurrent Protection I< (37) ........................................... 3-23
Directional Earth Fault Protection Idir> (67N) ...................... 3-23
Polarization .................................................................... 3-24
Modes for Different Network Types .............................. 3-24
Input Signal Selection .................................................... 3-25
Intermittent Earth Fault Detection .................................. 3-25
Two Independent Stages ................................................ 3-25
Inverse Operation Time .................................................. 3-26
Inverse Time Limitation ................................................. 3-26
Setting Groups ................................................................ 3-26
Recorded Values of the Latest Eight Faults ................... 3-29

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Earth Fault Protection I0> (50N/51N) ................................... 3-30
Input Signal Selection .................................................... 3-31
Intermittent Earth Fault Detection .................................. 3-31
Four or Six Independent Undirectional Earth Fault
Overcurrent Stages ................................................... 3-31
Inverse Operation Time (I0> stage only) ........................ 3-32
Inverse Time Limitation ................................................. 3-32
Setting Groups ................................................................ 3-32
Recorded Values of the Latest Eight Faults ................... 3-35
Intermittent Transient Earth Fault Protection Iot> (67NT) .... 3-35
Direction Algorithm ....................................................... 3-36
I
0Pick-up Sensitivity ...................................................... 3-36
Co-ordination with U0> back-up Protection ................... 3-36
Co-ordination with Normal Directional Earth Fault
Protection based on Fundamental Frequency Signals ... 3-36
Auto Reclosing ............................................................... 3-37
Intermittent Time ........................................................... 3-37
Operation Time Setting and Actual Operation Time ..... 3-37
Setting Groups ................................................................ 3-38
Recorded Values of the Latest Eight Faults ................... 3-39
Capacitor Bank Unbalance Protection .................................. 3-40
Compensation Method ................................................... 3-41
Compensation and Location ........................................... 3-41
Zero Sequence Voltage Protection U0> (59N) ...................... 3-44
Measuring the Residual Voltage .................................... 3-44
Two Independent Stages ................................................ 3-44
Setting Groups ................................................................ 3-44
Recorded Values of the Latest Eight Faults ................... 3-45
Thermal Overload Protection T> (49) .................................. 3-46
Thermal Model ............................................................... 3-46
Time Constant for Cooling Situation ............................. 3-47
Heat Capacitance, Service Factor and Ambient Temp. ... 3-47
Example of a Behavior in the Thermal Model ............... 3-48
Initial Temperature Rise After Restart ........................... 3-48
Alarm Function .............................................................. 3-48
Overvoltage Protection U> (59) ........................................... 3-50
Three Independent Stages .............................................. 3-51
Configurable Release Delay ........................................... 3-51
Configurable Hysteresis ................................................. 3-51
Setting Groups ................................................................ 3-51
Recorded Values of the Latest Eight Faults ................... 3-52
Undervoltage Protection U< (27) ......................................... 3-53
Blocking during VT Fuse Failure ................................... 3-53
Self Blocking at Very Low Voltage ............................... 3-53
Three Independent Stages .............................................. 3-54
Setting Groups ................................................................ 3-54
Recorded Values of the Latest Eight Faults ................... 3-55
Reverse Power and Underpower Protection P< (32) ............ 3-56

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Overfrequency and Underfrequency Protection f>, f<
(81H/81L) .................................................................... 3-57
Protection Mode for f>< and f><>< Stages ................... 3-57
Undervoltage Self Blocking of Underfrequency Stages .. 3-57
Initial Self Blocking of Underfrequency Stages ............. 3-57
Four Independent Frequency Stages .............................. 3-57
Setting Groups ................................................................ 3-57
Recorded Values of the Latest Eight Faults ................... 3-59
Rate of Change of Frequency (ROCOF) Protection df/dt (81R) ..3-59
Frequency Behavior During Load Switching ................. 3-59
Description of ROCOF Implementation ........................ 3-60
ROCOF and Frequency Over and Under Stages ............ 3-60
Definite Operation Time Characteristics ........................ 3-60
Inverse Operation Time Characteristics ......................... 3-61
Synchrocheck Protection (25) ............................................... 3-63
Circuit-breaker Failure Protection CBFP (50BF) ................. 3-70
Recorded Values of the Latest Eight Faults ................... 3-70
Programmable Stages (99) .................................................... 3-71
Eight Independent Stages ............................................... 3-73
Setting Groups ................................................................ 3-73
Recorded Values of the Latest Eight Faults ................... 3-73
Arc Fault Protection (50ARC/50NARC) (optional) ............. 3-74
Three Stages for Arc Faults ............................................ 3-74
Light Channel Selection ................................................. 3-74
Binary Input ................................................................... 3-75
Binary Output ................................................................. 3-75
Delayed Light Indication Signal .................................... 3-75
Pick-up Scaling .............................................................. 3-75
Recorded Values of the Latest Eight Faults ................... 3-77
Inverse Time Operation ........................................................ 3-77
Stage Specific Inverse Delay .......................................... 3-77
Operation Modes ............................................................ 3-77
Local Panel Graph .......................................................... 3-78
Inverse Time Setting Error Signal .................................. 3-78
Limitation ....................................................................... 3-78
Standard Inverse Delays IEC, IEEE, IEEE2, RI ............ 3-80
IEC Inverse Time Operation .................................... 3-80
IEEE/ANSI Inverse Time Operation ....................... 3-83
IEEE2 Inverse Time Operation ............................... 3-86
RI and RXIDG type Inverse Time Operation .......... 3-88
Free Parametrisation using IEC, IEEE and IEEE2
Equations ................................................................. 3-90
Programmable Inverse Time Curves .............................. 3-91
Inverse Time Setting Error Signal .................................. 3-91
Limitations ..................................................................... 3-91
Chapter 3 Protection Functions
(cont.)

Table of Contents v
857-UM001A-EN-P – July 2009
Chapter 4 Supporting Functions Event Log ................................................................................4-1
Event Enabling/Masking .................................................. 4-1
Event Buffer Overflow ..................................................... 4-2
Disturbance Recorder ............................................................. 4-2
Triggering the Recorder ................................................... 4-2
Reading Recordings ......................................................... 4-2
Number of Channels ........................................................ 4-3
Cold Load Pick-up and Inrush Current Detection .................. 4-5
Cold Load Pick-up ........................................................... 4-5
Application for Cold Load Detection ............................... 4-5
Inrush Current Detection .................................................. 4-5
Application for Inrush Current Detection ........................ 4-5
Voltage Sags and Swells ......................................................... 4-7
Voltage Interruptions .............................................................. 4-8
Current Transformer Supervision ......................................... 4-10
Voltage Transformer Supervision ......................................... 4-11
Circuit Breaker Condition Monitoring ................................. 4-12
Breaker Curve and its Approximation ........................... 4-12
Setting Alarm Points ...................................................... 4-13
Clearing “Operations Left” Counters ............................. 4-14
Operation Counters to Monitor the Wearing .................. 4-14
Logarithmic Interpolation .............................................. 4-14
Example of the Logarithmic Interpolation ..................... 4-15
Example of Operation Counter Decrementing ............... 4-15
Energy Pulse Outputs ........................................................... 4-17
Scaling Examples ........................................................... 4-18
System Clock and Synchronization .......................................4-20
Adapting Auto Adjust .................................................... 4-20
Time Drift Correction Without External Sync ............... 4-20
Synchronization with DI ................................................ 4-22
Synchronization Correction ............................................ 4-22
Sync Source .................................................................... 4-22
Deviation ........................................................................ 4-22
Auto-Lag/Lead ............................................................... 4-23
Running Hour Counter ......................................................... 4-23
Timers ................................................................................... 4-24
Combined Overcurrent Status ............................................... 4-25
Self-Supervision ................................................................... 4-27
Diagnostics ..................................................................... 4-27
Earth-Fault Location ............................................................. 4-29
Algorithm Functions ...................................................... 4-29

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Chapter 5 Measurement Functions Measurement Accuracy ...........................................................5-1
RMS Values ............................................................................ 5-2
RMS Currents ................................................................... 5-2
RMS Voltages .................................................................. 5-2
Harmonics and Total Harmonic Distortion (THD) ................. 5-3
Demand Values ....................................................................... 5-3
Minimum and Maximum Values ............................................ 5-4
Maximum Values of the last 31 days and 12 months ............. 5-5
Voltage Measurement Mode ................................................... 5-5
Power Calculation ................................................................... 5-6
Device Connected to Line-to-Line Voltages .................... 5-6
Device Connected to Line-to-Neutral Voltages ............... 5-7
Direction of Power and Current .............................................. 5-8
Symmetric Components .......................................................... 5-9
Primary, Secondary and Per Unit Scaling ............................ 5-12
Current Scaling ............................................................... 5-12
Per Unit [pu] Scaling ...................................................... 5-13
Voltage Scaling ..................................................................... 5-15
Per Unit [pu] Scaling of Line-to-Line Voltages ............. 5-16
Chapter 6 Control Functions Output Relays ..........................................................................6-1
Digital Inputs .......................................................................... 6-2
Virtual Inputs and Outputs ...................................................... 6-4
Output Matrix ......................................................................... 6-5
Blocking Matrix ...................................................................... 6-6
Controllable Objects ............................................................... 6-6
Object States ..................................................................... 6-7
Basic Settings for Controllable Objects ........................... 6-7
Output Signals of Controllable Objects ........................... 6-7
Settings for Read-only Objects ........................................ 6-8
Controlling with DI .......................................................... 6-8
Local/Remote Selection ................................................... 6-8
Auto-Reclose Function (79) ................................................... 6-9
Manual Closing .............................................................. 6-10
Manual Opening ............................................................. 6-10
Reclaim Time Setting ..................................................... 6-10
Support for 2 Circuit Breakers ....................................... 6-11
Blocking of AR Shots .................................................... 6-11
Starting AR Sequence .................................................... 6-11
Starting Sequence at Shot 2-5 & Skipping of AR Shots .... 6-11
Critical AR Request ....................................................... 6-12
Shot Active Matrix Signal .............................................. 6-12
AR Running Matrix Signal ............................................ 6-12
Final Trip Matrix Signals ............................................... 6-12
DI to Block AR Setting .................................................. 6-12
AR Info for Mimic Display Setting ................................ 6-12
Logic Functions .................................................................... 6-16

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Chapter 7 Communications Communication Ports ..............................................................7-1
Local Port ........................................................................ 7-1
Remote Port X9 ................................................................ 7-3
Extension Port .................................................................. 7-5
Optional 61850 Interface .................................................. 7-5
Communication Protocols ...................................................... 7-6
PC Communication .......................................................... 7-6
Modbus TCP and Modbus RTU........................................ 7-6
Probibus DP ..................................................................... 7-7
SPA-Bus ........................................................................... 7-9
IEC 60870-5-103 .............................................................. 7-9
DNP 3.0 .......................................................................... 7-11
IEC 60870-5-101 .............................................................7-12
TCP/IP ............................................................................ 7-14
External I/O (Modbus RTU master) ............................... 7-14
IEC 61850 ...................................................................... 7-14
DeviceNet ....................................................................... 7-14
Chapter 8 Applications Substation Feeder Protection .................................................. 8-1
Industrial Feeder Protection .................................................... 8-2
Parallel Line Protection .......................................................... 8-2
Ring Network Protection ........................................................ 8-4
Trip Circuit Supervision ......................................................... 8-4
Internal Parallel Digital Inputs ......................................... 8-4
Trip Circuit Supervision with One Digital Input .............. 8-5
Trip Circuit Supervision with Two Digital Inputs ........... 8-7
Chapter 9 Connections Rear Panel View ......................................................................9-1
Auxiliary Voltage ................................................................... 9-5
Serial Communication Connection .................................. 9-5
Pin Assignments of Communication Options .................. 9-7
Front Panel Connector .................................................... 9-10
Optional Two-Channel Arc Protection Card ........................ 9-11
Optional Digital I/O Card (DI19/DI20) ................................ 9-11
Block Diagrams .................................................................... 9-12
Block Diagrams of Option Modules ..................................... 9-13
Optional Arc Protection ................................................. 9-13
Connection Examples ........................................................... 9-14

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Chapter 10 Technical Data Connections .......................................................................... 10-1
Measuring Circuitry ....................................................... 10-1
Auxiliary Voltage ........................................................... 10-1
Digital Inputs .................................................................. 10-2
Trip Contacts .................................................................. 10-2
Alarm Contacts ............................................................... 10-2
Local Serial Communication Port .................................. 10-3
Remote Control Connection ........................................... 10-3
Arc Protection Interface (Option) .................................. 10-3
Tests and Environmental Conditions .................................... 10-4
Disturbance Tests ........................................................... 10-4
Test Voltages .................................................................. 10-4
Mechanical Tests ............................................................ 10-4
Environmental Conditions .............................................. 10-4
Casing ............................................................................. 10-5
Package .......................................................................... 10-5
Protection Stages .................................................................. 10-5
Non-Directional Current Protection ............................... 10-5
Overcurrent Stage I> (50/51) ................................... 10-5
Overcurrent Stage I>> and I>>> (50/51) ................. 10-6
Stall Protection Stage (48) ....................................... 10-6
Thermal Overload Stage T> (49) ............................. 10-7
Unbalance Stage I2> (46) ......................................... 10-7
Incorrect Phase Sequence I2>> (47) ......................... 10-7
Undercurrent Protection Stage I< (37) .................... 10-7
Unbalance/broken Connector Protection I2/I1> (46R) 10-8
Earth Fault Stage I0> (50N/51N) ............................. 10-8
Earth Fault Stage I0>>, I0>>>, I0>>>> (50N/51N) .. 10-9
Circuit-breaker Failure Protection ........................... 10-9
Directional Current Protection ..................................... 10-10
Directional Overcurrent Stages Idir> and Idir>> (67) . 10-10
Directional Overcurrent Stages Idir>>> and
Idir>>>> (67) ...................................................... 10-11
Directional Earth Fault Stages I0ϕ>, I0ϕ>> (67N) ... 10-12
Frequent Start Protection .............................................. 10-12
Frequent Start Protection N> (66) ......................... 10-12
Voltage Protection ........................................................ 10-13
Overvoltage Stages U>, U>> and U>>> (59) ........ 10-13
Undervoltage Stages U<, U<< and U<<< (27) ...... 10-13
Zero Sequence Voltage Stages U0> and U0>> (59N) .. 10-14
Frequency Protection ................................................... 10-14
Overfrequency and Underfrequency Protection .... 10-14
Underfrequency Stages f< and f<< ........................ 10-15
Rate of Change of Frequency (ROCOF) Stage ..... 10-15

Table of Contents ix
857-UM001A-EN-P – July 2009
Power Protection .......................................................... 10-16
Reverse Power and Under-Power Stages ............... 10-16
Synchrocheck Function ................................................ 10-16
Circuit-Breaker Failure Protection ............................... 10-17
Arc Fault Protection Stages (Option) ........................... 10-17
Arc Protection Stage ArcI> (50AR), Option ..........10-17
Arc Protection Stage ArcI0> (50AR), Option ........ 10-18
Arc Protection Stage ArcI02> (50AR), Option ....... 10-18
Supporting Functions .......................................................... 10-18
Inrush Current Detection (68) ................................ 10-18
Disturbance Recorder (DR) .......................................... 10-19
Transformer Supervision .............................................. 10-19
Current Transformer Supervision .......................... 10-19
Voltage Transformer Supervision .......................... 10-19
Voltage Sag and Swell ................................................. 10-20
Voltage Interruptions ................................................... 10-20
Chapter 11 List of Abbreviations and Symbols .......................................11-1
Chapter 12 Installation Mounting Instructions ...........................................................12-1
Dimensions ........................................................................... 12-2
Abbreviations and
Symbols

x Table of Contents
857-UM001A-EN-P – July 2009

Chapter 1
857-UM001A-EN-P – July 2009
Overview
Introduction The Allen-Bradley 857 motor and feeder protection device includes
all the essential protection functions needed to protect feeders and
motors in distribution networks of utilities, heavy industry, power
plants and offshore applications. Further, the device includes many
programmable functions, such as arc protection (option), thermal,
trip circuit supervision and circuit breaker protection and
communication protocols for various protection and communication
situations.
This User Manual contains general descriptions of the functions of
the protection relay as well as installation and operation instructions. It
also includes instructions for parameterization and configuration of the
relay and instructions for changing settings.
This manual also includes detailed protection function descriptions
as well as application examples and technical data sheets.
Main Relay Features The main features of the Allen-Bradley 857 device are:
•Fully digital signal handling with a powerful 16-bit
microprocessor, and high measuring accuracy on all the setting
ranges due to a 16-bit A/D conversion technique
•Wide setting ranges for the protection functions can reach a
sensitivity of 0.5%
•Integrated fault location for short-circuit faults
•The device can be matched to the requirements of the application
by disabling the functions that are not needed
•Flexible control and blocking possibilities due to digital signal
control inputs (DI) and outputs (DO)
•Easy adaptability of the device to various substations and alarm
systems due to flexible signal-grouping matrix in the device
•Possibility to control six objects (e.g. circuit-breakers,
disconnectors)
•Status of eight objects (e.g. circuit breakers, disconnectors,
switches)
•Freely configurable display with six selectable measurement
values
•Freely configurable interlocking schemes with basic logic
functions

1-2 Introduction
857-UM001A-EN-P – July 2009
•Recording of events and fault values into an event register from
which the data can be read via a keypad and a local HMI or by
means of a PC based configuration software
•All settings, events and indications are in non-volatile memory.
•Easy configuration, parameterization and reading of information
via local HMI, or with a SetPointPS user interface
•Easy connection to automation systems via versatile serial
connection and several available communication protocols
•Built-in, self-regulating ac/dc converter for auxiliary power supply
from any source within the range from 40 to 265 VDC or VAC.
•Built-in disturbance recorder for evaluating all the analogue and
digital signals
The comprehensive protection functions of the relay make it ideal for
utility, industrial, marine and off-shore power distribution
applications. The relay features the following protection functions.
Table 1.1 – List of Protection Functions
IEEE/
ANSI code IEC symbol Function name Note
50/51 3I>, 3I>>, 3I>>> Overcurrent protection
67 Idir>, Idir>>,
Idir>>>, Idir>>>> Directional overcurrent protection
46R I2/I1> Broken conductor protection
46 I2> Current unbalance protection
47 I2>> Phase reversal / incorrect phase
sequence protection
48 Ist> Stall protection
66 N> Frequent start protection
Only available
when application
mode is motor
protection
37 I< Undercurrent protection
67N I0ϕ>, I0ϕ>> Directional earth fault protection
50N/51N I0>, I0>>, I0>>>,
I0>>>> Earth fault protection
67NT I0T Intermittent transient earth fault
protection
Capacitor bank unbalance
protection
59N U0>, U0>> Residual voltage protection
49 T> Thermal overload protection
59 U>, U>>, U>>> Overvoltage protection
27 U<, U<<, U<<< Undervoltage protection
32 P<, P<< Reverse and underpower
protection
81H/81L f><, f>><< Overfrequency and
underfrequency protection
Main Relay Features (cont.)

Introduction 1-3
857-UM001A-EN-P – July 2009
Table 1.1 – List of Protection Functions (cont.)
IEEE/
ANSI code IEC symbol Function name Note
81L f<, f<< Underfrequency protection
81R df/dt Rate of change of frequency
(ROCOF) protection
25 ∆f, ∆U, ∆φ Synchrocheck
50BF CBFP Circuit-breaker failure protection
99 Prg1...8 Programmable stages
50ARC/
50NARC ArcI>, ArcI01>,
ArcI02> Optional arc fault protection
I/O
110 kV network
20 kV overhead line
20 kV cable
network
Power
plants
400kV/200 kV
transmission
network
Distribution
substation
230/400V
Distribution transformer
230/400V
Secondary
substation
(distribution
transformer)
Remote control
Protection
relay
Protection
relay
Circuit
breaker
Transmission
substations
Remote Control Interface
VAMP255 S ll k
Figure 1.1 – Application of the Feeder and Motor Protection Device
Further the relay includes a disturbance recorder. Arc protection is
optionally available.
The relay communicates with other systems using common
protocols, such as the DeviceNet, Modbus RTU, Modbus TCP,
Ethernet, Profibus DP, IEC 60870-5-103, IEC 60870-5-101, IEC
61850, SPA bus and DNP 3.0.

1-4 Introduction
857-UM001A-EN-P – July 2009
User Interface
The relay can be controlled in three ways:
•Locally with the push-buttons on the relay front panel
•Locally using a PC connected to the serial port on the front panel
or on the rear panel of the relay (both cannot be used
simultaneously)
•Via remote control over the remote control port on the relay rear
panel.
Operating Safety
ATTENTIONATTENTION
The terminals on the rear panel of the relay may
carry dangerous voltages, even if the auxiliary
voltage is switched off. A live current
transformer secondary circuit must not be
opened. Disconnecting a live circuit may cause
dangerous voltages! Any operational measures
must be carried out according to national and
local handling directives and instructions.
IMPORTANTIMPORTANT Carefully read through all operation
instructions before any operational measures
are carried out.

Chapter 2
857-UM001A-EN-P – July 2009
Local Panel User Interface
Relay Front Panel The figure below shows, as an example, the front panel of the Allen-
Bradley 857 relay and the location of the user interface elements
used for local control.
Figure 2.1 – Front Panel of Allen-Bradley 857 Relay
1. LCD dot matrix display
2. Keypad
3. LED indicators
4. RS-232 serial communication port for PC
Display
The relay is provided with a backlit 128x64 LCD dot matrix
display. The display enables showing 21 characters in one row
and eight rows at the same time. The display has two different
purposes: one is to show the single line diagram of the relay with
the object status, measurement values, identification etc. (Figure
2.2). The other purpose is to show the configuration and
parameterization values of the relay (Figure 2.3).
Figure 2.2 – Sections of the LCD Matrix Display

2-2 Local Panel User Interface
857-UM001A-EN-P – July 2009
1. Freely configurable single-line diagram
2. Five controllable objects
3. Six object statuses
4. Bay identification
5. Local/Remote selection
6. Auto-reclose on/off selection (if applicable)
7. Freely selectable measurement values (max. six values)
10
11 9
13
8
12
Figure 2.3 – Sections of the LCD Matrix Display
8. Main menu column
9. The heading of the active menu
10. The cursor of the main menu
11. Possible navigating directions (push buttons)
12. Measured/setting parameter
13. Measured/set value
Backlight Control
Display backlight can be switched on with a digital input, virtual
input or virtual output. LOCALPANEL CONF/Display backlight
ctrl setting is used for selecting trigger input for backlight control.
When the selected input activates (rising edge), display backlight is
set on for 60 minutes.

Local Panel User Interface 2-3
857-UM001A-EN-P – July 2009
Menu Navigation and Pointers
1. Use the arrow keys UP and DOWN to move up and down in the
main menu, that is, on the left-hand side of the display. The
active main menu option is indicated with a cursor. The options
in the main menu items are abbreviations, e.g. Evnt = events.
2. After any selection, the arrow symbols in the upper left corner of
the display show the possible navigating directions (applicable
navigation keys) in the menu.
3. The name of the active submenu and a possible ANSI code of
the selected function are shown in the upper part of the display,
e.g. CURRENTS.
4. Further, each display holds the measured values and units of one
or more quantities or parameters, e.g. ILmax 300A.
Keypad
You can navigate in the menu and set the required parameter
values using the keypad and the guidance given in the display.
Furthermore, the keypad is used to control objects and switches
on the single line diagram display. The keypad is composed of
four arrow keys, one cancel key, one enter key and one info key.
Figure 2-4 – Keys on the Keypad
1. Enter and confirmation key (ENTER)
2. Cancel key (CANCEL)
3. Up/Down [Increase/Decrease] arrow keys (UP/DOWN)
4. Keys for selecting submenus [selecting a digit in a numerical
value] (LEFT/RIGHT)
5. Additional information key (INFO)
NOTE: The term, which is used for the buttons in this manual,
is inside the rounded brackets.

2-4 Local Panel User Interface
857-UM001A-EN-P – July 2009
Operation Indicators
The relay is provided with eight LED indicators:
Power
Error
Com
Alarm
Trip
A
B
C
Figure 2.5 – Operation Indicators of the Relay
Table 2.1 – Operation Indicators
LED indicator Meaning Remarks
Power LED lit The auxiliary power has been
switched on Normal operation state
Error LED lit Internal fault, operates in parallel
with the self supervision output
relay
The relay attempts to reboot
[REBOOT]. If the error LED
remains lit, call for
maintenance.
Com LED lit or
flashing The serial bus is in use and transferring information Normal operation state
Alarm LED lit One or several signals of the
output relay matrix have been
assigned to output LA and the
output has been activated by one
of the signals. (For more
information about output matrix,
please see “Configuring Digital
Outputs DO”.
The LED is switched off when
the signal that caused output
Al to activate, e.g. the START
signal, is reset. The resetting
depends on the type of
configuration, connected or
latched.
Trip LED lit One or several signals of the
output relay matrix have been
assigned to output Tr, and the
output has been activated by one
of the signals. (For more
information about output relay
configuration, please see
“Configuring Digital Outputs
DO”).
The LED is switched off when
the signal that caused output
Tr to activate, e.g. the TRIP
signal, is reset. The resetting
depends on the type of
configuration, connected or
latched.
A- C LED lit Application-related status
indicators. Configurable