Siemens bt300 Operator's Manual page 76

Chapter 4 - Parameters and Menu Structure
Parameters (M3)
Motor thermal load (P3.9.10)
Setting the value to 130% means that the nominal temperature will be reached with 130% of the motor's nominal
current.
Stall Protection (P3.9.11 through P3.9.14)
The motor stall protection protects the motor from short-time overload situations such as one caused by a stalled
shaft. The reaction time of the stall protection can be set shorter than that of the motor thermal protection. The stall
state is defined with two parameters: Stall Current (P3.9.12) and Stall Frequency Limit (P3.9.14). If the current is
higher than the set limit and the output frequency is lower than the set limit, the stall state is true. There is actually
no real indication of the shaft rotation. Stall protection is a type of over-current protection.
Stall current (P3.9.12)
The current can be set to 0.0...2*IL. For a stall stage to occur, the current must have exceeded this limit. See the
following figure. If Motor current limit (P3.1.1.7) is changed, this parameter is automatically calculated to 90% of the
current limit.
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Figure 19: Motor Temperature Calculation.
NOTE:
To guarantee desired operation, this limit must be set below the current limit.
Siemens BT300 HVAC Drive DPD01809
2016-06-07