Rockwell Automation 193-EC1_2_3_5, 193-ECPM,592-EC1_2_3_5 E3 and E3 Plus Solid-State Overload Relay User Manual - Manual (Page 45)

Rockwell Automation Publication 193-UM002I-EN-P - December 2011 45
Chapter
3
Protective Trip & Warning Functions
Introduction
The purpose of this chapter is to provide detailed information regarding the
protective trip and warning functions of the E3 Overload Relay. In this chapter,
you will find considerable mention given to programming parameters as they
relate to these functions. For complete descriptions of the programming
parameters, refer to Chapter 5—Programmable Parameters.
Trip Enable
Trip Enable, Parameter 24, allows the installer to enable or disable the desired
protective functions separately. The overload, phase loss, and communication
fault trip functions are enabled from the factory.
Warning Enable
Warning Enable, Parameter 25, allows the installer to enable or disable the desired
warning functions separately. All warning functions are disabled from the factory.
Overload Protection
The E3 Overload Relay provides overload protection through true RMS current
measurement of the individual phase currents of the connected motor. Based on
the maximum current measured and the programmed FLA Setting and Trip
Class, a thermal model that simulates the actual heating of the motor is
calculated. The percent thermal capacity utilized, Parameter 9, reports this
calculated value and can be read via the DeviceNet network.
Overload Trip
The E3 Overload Relay will trip with an overload indication if:
• no trip currently exists,
• overload protection is enabled, and
IMPORTANT The E3 Overload Relay requires overload trip protection to be enabled at
all times. The E3 Plus Overload Relay requires either overload or PTC trip
protection to be enabled at all times.
ATTENTION: To avoid unexpected behavior of the outputs, the Trip
Enable settings should not be altered during the machine operation.
Doing so may result in an unintended actuation of controlled industrial
equipment with potential for machine damage or serious injury to
personnel.