Rockwell Automation 592- E300 Overload Relay User Manual - Manual (Page 80)

80 Rockwell Automation Publication 193-UM015B-EN-P - June 2014
Chapter 5 Protective Trip and Warning Functions
Overload Protection
The E300 Electronic Overload Relay provides overload protection through true
RMS current measurements of the individual phase currents of the connected
motor. Based on the highest current measured, the programmed FLA Setting,
and Trip Class, a thermal model that simulates the actual heating of the motor is
calculated. Percent Thermal Capacity Utilized (Parameter 1) reports this
calculated value and can be read via the communications network.
Overload Trip
The E300 Electronic Overload Relay will trip with an overload indication if:
• No trip currently exists
• Overload trip protection is enabled
• Current is present
• % Thermal Capacity Utilized reaches 100%
If the E300 Electronic Overload Relay trips on an overload, the following will
occur:
• The TRIP/WARN LED will flash a red short-1 blink pattern,
• Bit 0 in Current Trip Status (Parameter 4) will set to 1
• Bit 0 in Device Status 0 (Parameter 20) will set to 1
• Any relay outputs configured as a Trip Relay will open
• Any relay outputs configured as a Control Relay will open
• Any relay outputs configured as a Trip Alarm will close
• Any relay outputs configured as a Normal Relay will be placed in their
Protection Fault state (if so programmed)