Rockwell Automation SP600 User Manual Version 3.0 User Manual
Page 23
About the Drive
2-9
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Software current limit
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Heatsink temperature protection
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Overload protection IT (see Drive Overload Protection, section
2.3.13)
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Thermal manager
2.3.13 Drive Overload Protection
The drive thermal overload will protect the drive power stage while
maintaining performance as long as the drive temperature and
current ratings are not exceeded.
The drive will monitor the temperature of the power module based
on a measured temperature and a thermal model of the IGBT. As
the temperature rises, the drive may lower the PWM frequency to
decrease the switching losses in the IGBT. If the temperature
continues to rise, the drive may reduce current limit to try to
decrease the load on the drive. If the drive temperature becomes
critical, the drive will generate a fault.
If the drive is operated in a low ambient condition, the drive may
exceed rated levels of current before the monitored temperature
becomes critical. To guard against this situation, the drive thermal
overload also includes an inverse time algorithm. When this
scheme detects operation beyond rated levels, current limit may be
reduced or a fault may be generated.