Underload protection, Jam warning – Rockwell Automation 193-EDN E1Plus Overload Relays - DeviceNet Module User Manual
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Publication 193-UM006A-EN-P – October 2005
2-4 Protection Functions
• 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 21, Jam Warn Level, allows the installer to define the current at
which the DeviceNet Module will indicate a warning. It is user-adjustable from
100…600% FLA.
The DeviceNet 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 10, 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 34 (OUTA Pr FltState) and parameter 35 (OUTA
Pr FltValue).
IMPORTANT
The jam inhibit timer starts after the load current
transitions from 0 A to 30% FLA. The DeviceNet 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.