Rockwell Automation 592- E300 Overload Relay User Manual - Manual (Page 103)

Rockwell Automation Publication 193-UM015B-EN-P - June 2014 103
Protective Trip and Warning Functions Chapter 5
Table 86 - Underload Trip Delay (Parameter 256)
Underload Trip Level
Underload Trip Level (Parameter 257) allows the installer to define the current at
which the E300 Electronic Overload Relay will trip on an underload. It is user-
adjustable from 10…100% of the FLA Setting (Parameter 171).
Table 87 - Underload Trip Level (Parameter 257)
Underload Warning
The E300 Electronic Overload Relay will indicate an underload warning if:
• No warning currently exists
• Underload Warning is enabled
• Current is present
• Underload Inhibit Time has expired
• The minimum phase current is less than the Underload Warning Level
When the Underload Warning conditions are satisfied, the:
Default Value 5.0
Minimum Value 0.1
Maximum Value 25.0
Parameter Type USINT
Size (Bytes) 1
Scaling Factor 10
Units Sec
Default Value 50
Minimum Value 10
Maximum Value 100
Parameter Type USINT
Size (Bytes) 1
Scaling Factor 1
Units %FLA
IMPORTANT The Underload Inhibit Timer starts after the maximum phase of load current
transitions from 0 A to 30% of the device’s minimum FLA setting. The E300
Electronic Overload Relay does not begin monitoring for an underload
condition until the Underload Inhibit Time expires.
IMPORTANT For any given application, the practical limit of the Underload Trip Level
(Parameter 246), will be dependent on the FLA Setting and the lower limit of
the E300 Electronic Overload Relay’s current measurement capability.