Rockwell Automation 193-EC4 EC4 Current Monitoring Relay User Manual - Manual (Page 38)

Rockwell Automation Publication 193-UM011A-EN-P - September 2010 39
Protective Trip and Warning Functions Chapter 3
Ground Fault Setting Range
EC4 Current Monitoring Relays using the external ground fault sensor (Cat. no.
193-CBCT_) have four sensing ranges, which are selectable via the
GF Sensing
Range parameter.
Parameter 106, GF Sensing Range (Series C and later)
• 20…100 mA (For resistive loads only. For motor load information, please
consult your local Rockwell Automation sales office or Allen-Bradley
distributor.)
• 100…500 mA
• 200 mA …1.0 A
• 1.0…5.0 A
Ground Fault Trip
The EC4 Current Monitoring Relay will trip with a ground fault indication if:
• No trip currently exists
• Ground fault protection is enabled
• GF Inhibit Time has expired
• GF Current is equal to or greater than the GF Trip Level for a time period
greater than the GF Trip Delay
If the EC4 Current Monitoring Relay trips on a ground fault, the following will
occur:
• The TRIP/WARN LED will flash a red 4-blink pattern
• Bit 3 in Parameter 14, Trip Status, will go to “1”
• Bit 0 of Parameter 21, Device Status, will go to “1”
• The Trip Relay contact will open
• The outputs will be placed in their Protection Fault state (if so
programmed)
Parameter 35, GF Inhibit Time, allows the installer to inhibit a ground fault trip
from occurring during the motor starting sequence and is adjustable from 0…250
seconds.
Parameter 36, GF Trip Delay, allows the installer to define the time period a
ground fault condition must be present before a trip occurs. It is adjustable from
0.0…25.0 seconds.
IMPORTANT The Protection Fault State of OUT A and OUT B is defined by Parameter
65 (OUTA Pr FltState), Parameter 66 (OUTA Pr FltValue), Parameter 71
(OUTB Pr FltState), and Parameter 72 (OUTB Pr FltValue).