Rockwell Automation 825 Smart Motor Manager User Manual - Manual (Page 58)

3-25 Functions
Publication 825-UM001B-EN-P January 2001
Note: If the starting current is below 1.2 FLC, then the “Monitoring the Start Time”
function must be activated. After the set max. starting Time has elapsed, the “High
Overload/Stall” function will become active.
Applications:
• Slip ring motors
• Soft starters
• Motor protection with “non-fail-safe mode”, after a control voltage failure
Underload
Motors that are cooled by the medium handled (e.g., fans, submersible pumps) can become
overheated despite being underloaded. This can be a result of the absence of the medium or
insufficient medium (due to clogged filters, closed valves, etc.). Often these motors are
installed in inaccessible places, so repair is lengthy and expensive.
The consumption of less than a preset, application-specific amount of current may indicate a
mechanical defect in the installation (e.g., torn conveyor belt, damaged fan blades, broken
shafts or worn tools). Such conditions do not harm the motor, but they do lead to loss of
production. Rapid fault detection helps to minimize damage.
The underload protection trip time can be delayed following each start to prevent tripping.
The warning is actuated as soon as the underload threshold is reached.
Application
• Submersible pumps
• Fans
• Conveyor systems
• Detection of fractures in mechanical transmission system
ATTENTION
!
It is essential to set the “Warning” response level to a value less than
the “Trip” response level.