Rockwell Automation 193-EPRB Profibus Side Mount Module for the E1 Plus Overload Relay User Manual - Manual (Page 11)

Publication 193-UM010A-EN-P – January 2008
Protection Functions 2-3
The PROFIBUS Module will command the E1 Plus Overload Relay to trip if all the following
conditions are met:
• No trip currently exists
• Jam Protection is enabled
• Jam Inhibit Time has expired
• The motor current is greater than the Jam Trip Level for a time period greater than the
Jam Trip Delay
When the conditions for a jam trip are satisfied, the following will occur:
• Bit 2 in Parameter 3, Trip Status, will go to “1”
• Bit 0 in Parameter 5, Device Status, will go to “1”
• The E1 Plus Overload Relay's trip relay contacts (95 and 96) will open
• Out A will be placed in their Protection Fault State (if so programmed)
Jam Warning
Parameter 16, Jam Warn Level, allows the installer to define the current at which the PROFIBUS
Module will indicate a warning. It is user-adjustable from 100…600% FLA.
The PROFIBUS Module will indicate a Jam warning if:
• No warning currently exists
• Jam Warning is enabled
• Jam Inhibit Time has expired
• The motor current is equal to or greater than the Jam Warn Level
When the Jam Warning conditions are satisfied, the following will occur:
• Bit 2 in Parameter 4, Warning Status, will go to “1”
• Bit 1 in Parameter 5, Device Status, will go to “1”
Underload Protection
Motor current less than a specific level may indicate a mechanical malfunction in the installation,
such as a torn conveyor belt, damaged fan blade, broken shaft, or worn tool. Such conditions
may not harm the motor, however, rapid detection may help to minimize equipment damage
and loss of production.
IMPORTANT
The Protection Fault State of OUT A is defined by parameter 22
(OUTA Pr FltState) and parameter 23 (OUTA Pr FltValue).
IMPORTANT
The jam inhibit timer starts after the load current transitions from 0 A to
30% FLA. The PROFIBUS Module does not begin monitoring for a jam
condition until the Jam Inhibit Time expires.
IMPORTANT
The Jam Warning function does not include a time delay feature. Once
the Jam Inhibit Time has expired, the Jam Warning indication is
instantaneous.