Step 1: Gather Required Information; Step 2: Review Required Information - Allen-Bradley 857 Quick Start Manual

Step 1: Gather Required
Information
Step 2: Review Required
Information
Installation
Before you apply power to the 857 Protection System for the first time, you
must obtain the specific information about your application.
• Selection of the appropriate protective mode for the 857 Protection
System: Motor or Feeder protective mode.
• The motor (feeder) nameplate data to determine your protective
functions and I/O.
• Obtain the current transformer and, if applied, voltage transformer data.
• The wiring configuration to the input and output relays on the
Protection System to determine the alarm and trip function
annunciation.
Review the minimum required information from Step 1 to verify the
requirements for the protective parameters before powering up your Protection
System. The required data and protective elements that are selected varies
depending on the connected load and the application mode selected.
This minimum data is critical for the selection of the proper minimum initial
protective settings in the Protection System.
Table 14 - Typical Minimum Motor-protection Applications Data
Motor/ Device ID
Motor Full Load Current
Motor Locked Rotor Current
Current Transformer Primary amps
Current Transformer Secondary amps
Voltage Transformer Primary Voltage
Voltage Transformer Secondary Voltage
Ground Fault CT Primary amps
Ground Fault CT Secondary amps
Rockwell Automation Publication 857-QS001B-EN-P - April 2017
Chapter
Motor 33
For example, 80 A
490 A
100
5
4160
120
100
1
4
29