Multilin 469 Motor Management Relay ... - GE Digital Energy

CHAPTER 1: GETTING STARTED
1.4 Application Example
1.4.1 Description
The 469 Motor Management Relay contains many features designed to accommodate a
wide range of motor management applications. This chapter is provided to guide you, the
first-time user, through a real-world application.
The following is typical example of how to determine the relay settings for a specific motor
that has been applied conservatively. This is only an example and may not address all
issues relating to your specific application. It is recommended that your local protection
engineer determine the settings for your motor protective relaying application. Refer to
following figures for schematic diagrams related to this example.
Important points to keep in mind before developing settings for any multifunction
numerical device like the 469 Motor Management Relay:
• Gather system data, including, but not limited to:
– CT primary and secondary ratings for all the CTs used to feed the relay
– motor name plate data
– motor operating curves (typical set shown below)
Time (sec.)
1000.000
100.000
10.000
1.000
0 500 1,000 1,500 2,000 2,500
Current (Amps)
FIGURE 1–1: Typical Motor Curves
806553A1.CDR
469 MOTOR MANAGEMENT RELAY – INSTRUCTION MANUAL 1–17