134 Rockwell Automation Publication 193-UM015D-EN-P - February 2015
Chapter 6 Protective Trip and Warning Functions
Outside USA and Canada Guidelines
• Maximum Continuous Rated (MCR) Motors: Program the FLA setting
to the full-load current rating on the printed nameplate.
• Star-Delta (Y-Δ) Applications: Follow the MCR instructions, except
divide the full-load current rating on the printed nameplate by 1.73.
Trip Class
Trip Class is the second of two parameters that affect the E300 Electronic
Overload Relay’s thermal capacity utilization algorithm. Trip class is defined as
the maximum time (in seconds) for an overload trip to occur when the motor’s
operating current is six times its rated current. The E300 Electronic Overload
Relay offers an adjustable trip class range of 5…30. Enter the application trip class
into Trip Class (Parameter 172).
Table 164 - Trip Class (Parameter 172)
Trip Curves
The following figures illustrate the E300 Electronic Overload Relay’s time-
current characteristics for trip classes 5, 10, 20, and 30.
Trip Class (Parameter 172)
Default Value 10
Minimum Value 5
Maximum Value 30
Parameter Type USINT
Size (Bytes) 1
Scaling Factor 1
Units