Protection Function Enable Types - Siemens SINAMICS PERFECT HARMONY GH180 Function Manual

Advanced Motor Protection Parameters

4.3 Protection Function Enable Types

4.3 Protection Function Enable Types
There are four types of enables used to control startup and disabling of the protection functions.
They are: Startup Time, Minimum Speed Enable, Minimum Speed Reset, and Fixed Torque
Pulsation Minimum Speed Enable.
The following paragraphs describe the operation of the various enables.
1. Startup Time is used to delay the startup of the protection function from the time that the run
command is issued. Following startup, the protection function will remain disabled until the
startup time has elapsed. Once the Startup Time has been met, the protection function will
be enabled unless another startup function continues to disable the protection function. The
startup time delay will be repeated if the drive is stopped and then started again.
2. Minimum Speed Enable is used to delay the startup of the protection function until the
machine achieves a minimum speed. Once the speed of the machine exceeds the Minimum
Speed Enable setting, the function is enabled and will remain enabled until the drive is
stopped (stop command, trip, etc.) unless another startup function continues to disable the
protection function (such as Startup Time). The function will remain enabled even if the
speed is reduced below the Minimum Speed Enable setting once that setting has been
exceeded for the first time. The Minimum Speed Enable is reset when the drive is stopped,
and the minimum speed will have to be reached again if the drive is stopped and then started
again.
3. Minimum Speed Reset is used to disable a protection function when the speed demand is
less than a specified value. When the demand setting is below the Minimum Speed Reset
setting, the protection function is reset. Any startup time delay or minimum speed enable will
be reset and the conditions of those enables will have to be met before the protection
function will be enabled again.
4. Fixed Torque Pulsation Minimum Speed Enable is a unique enable applicable only to the
excessive torque pulsation protection function. The setting resets the protection when the
motor speed is below the setting. This setting should be used to avoid trips due to conditions
where low motor speed is likely to result in false trips due to the finite sampling window of
the torque pulsation function.
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Advanced Motor Protection for Variable Speed Operation
Manual, AA, A5E46373908A