Rockwell Automation Publication 193-UM015E-EN-P - October 2015 381
Protective Trip and Warning Functions Chapter 6
Table 307 - Under Frequency Trip Level (Parameter 371)
Under Frequency Warning
The E300 relay indicates an Under Frequency warning if:
• No warning currently exists
• Under Frequency Warning is enabled
• Voltage is present
• Under Frequency Inhibit Time has expired
• The voltage frequency is equal to or less than the Under Frequency
Wa
rn
in g L e vel
When the Under Frequency Warning conditions are satisfied, the:
• TRIP/WARN LED flashes a yellow 1-long / 5-short blink pattern
• Bit 4 in Voltage Warning Status (Parameter 11) sets to 1
• Bit 1 in Device Status 0 (Parameter 20) sets to 1
• Any relay outputs configured as a Warning Alarm close
Under Frequency Warn Level
• Under Frequency Warn Level (Parameter 372) allows you to define the
frequency at which the E300 relay indicates a warning. It is user-
adjustable from 46…65 Hz.
Table 308 - Under Frequency Warn Level (Parameter 372)
Default Value 57
Minimum Value 46
Maximum Value 65
Parameter Type USINT
Size (Bytes) 1
Scaling Factor 1
Units Hz
The Under Frequency Inhibit Time starts after a phase voltage transitions from
0V to 20V L-L. The E300 relay does not begin monitoring for an under
frequency condition until the Under Frequency Inhibit Time expires.
Default Value 58
Minimum Value 46
Maximum Value 65
Parameter Type USINT
Size (Bytes) 1
Scaling Factor 1
Units Hz
To Next Page
Loading...
