Specifications

Altivar
®
31 Adjustable Speed AC Drives
Functions
© 2004–2005 Schneider Electric All Rights Reserved
48
4/2005
This function is suited to machines or installations in continuous operation or
without monitoring, and where a restart will not endanger equipment or
personnel in any way.
Derated operation in the event of an overvoltage
The line voltage monitoring threshold is lowered to 50% of the motor voltage.
A line reactor must be used, and drive performance is not guaranteed.
Resetting the fault relay
The fault relay is energized when the drive is powered up and no faults are
present.
It contains a C/O common point contact.
The fault is resettable in one of the following ways:
• by powering down until the On LED extinguishes, then switching the power
back on
• by assigning a logic input to the Reset Faults function
• by the Automatic Restart function, if configured
Operating time reset to zero
The drive operating time can be reset to zero.
Motor thermal protection
The theoretical temperature rise of the motor is continuously calculated to
provide indirect thermal protection.
Motor thermal protection is adjustable from 0.2 to 1.5 times the nominal drive
current. This function is suited to applications with self-cooled motors.
10,000
( 2 h 45)
1,000
100
0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 1.5 1.6
50201013
5 Hz
( 16 mn)
Motor thermal protection curves
Motor current/ItH
t
Trip time in seconds
Courtesy of Steven Engineering, Inc.-230 Ryan Way, South San Francisco, CA 94080-6370-Main Office: [phone]-Outside Local Area: [phone]-www.stevenengineering.com