Rockwell Automation Allen-Bradley E300, User Manual

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168 Rockwell Automation Publication 193-UM015D-EN-P - February 2015
Chapter 6 Protective Trip and Warning Functions
Table 205 - L3 Under Current Trip Level (Parameter 273)
L3 Under Current Warning
The E300 Electronic Overload Relay indicates an L3 Under Current warning if:
• No warning currently exists
• L3 Under Current Warning is enabled
• Current is present
• The Under Current Inhibit Timer has expired
• L3 Percent FLA (Parameter 49) is less than the L3 Under Current
Warning Level
When the L3 Under Current Warning conditions are satisfied, the:
• TRIP/WARN LED flashes a yellow 10-short blink pattern
• Bit 9 in Current Warning Status (Parameter 10) sets to 1
• Bit 1 in Device Status 0 (Parameter 20) sets to 1
• Any relay outputs configured as a Warning Alarm close
L3 Under Current Warning Level
L3 Under Current Warning Level (Parameter 274) allows you to define the
current at which the E300 Electronic Overload Relay indicates a L3 Under
Current warning. It is user-adjustable from 10…100% for the FLA Setting
(Parameter 171).
Default Value 35
Minimum Value 10
Maximum Value 100
Parameter Type USINT
Size (Bytes) 1
Scaling Factor 1
Units %FLA
IMPORTANT
The Under Current Inhibit Timer starts after the maximum phase of load
current transitions from 0 A to 30% of the minimum FLA setting of the device.
The E300 Electronic Overload Relay does not begin monitoring for an
undercurrent condition until the Under Current Inhibit Time expires.
IMPORTANT
For any given application, the practical limit of the L3 Under Current Trip Level
(Parameter 273) is dependent on the FLA Setting and the lower limit of the
E300 Electronic Overload Relay’s current measurement capability