Undercurrent trip – Rockwell Automation 193-EC4 EC4 Current Monitoring Relay User Manual User Manual

Page 41

Rockwell Automation Publication 193-UM011A-EN-P - September 2010

Chapter 3 Protective Trip and Warning Functions

Parameter 48,

UL Warn Level, allows the installer to define the current at which

the EC4 Current Monitoring Relay will indicate a warning.

Undercurrent Trip

The EC4 Current Monitoring Relay will trip with an undercurrent indication if:

• The current in any of the phases is lower than the current specified for the

corresponding

UC Trip Level parameter (Parameter 108 for L1, parameter

111 for L2, & parameter 114 for L3)

• No trip currently exists

If the EC4 Current Monitoring Relay trips on an undercurrent condition, the
following will occur:

• The TRIP/WARN LED will flash a red blinking pattern depending on

which phase encountered the undercurrent condition
–

2 blinks for L1 undercurrent

–

3 blinks for L2 undercurrent

–

4 blinks for L3 undercurrent

• Parameter 14, Trip Status, will change

–

Bit 1 will go to "1" for L1 undercurrent

–

Bit 2 will go to "1" for L2 undercurrent

–

Bit 3 will go to "1" for L3 undercurrent

• Bit 0 in Parameter 21, Device Status, will go to "1"
• The outputs will be placed in their Protection Fault state (if so

programmed)

Parameter 45,

UL Inhibit Time, allows the installer to inhibit an underload trip

from occurring during the motor starting sequence and is adjustable from 0…250
seconds.

IMPORTANT

The Underload Warning function does not include a time delay feature.
Once the UL Inhibit Time has expired, the Underload warning indication
is instantaneous.

IMPORTANT

For any given application, the practical limit of UL Warn Level (Parameter
48) will be dependent upon the FLA setting and the lower limit of the EC4
Current Monitoring Relay’s current measurement capability. See Table 20
- on page 83

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 Flt Value).