I2t motor overload protection Description WARNING For stepper motors only the nominal current but no maximum current is specified. Therefore the usage of I2t with stepper motors is used at the users own risk I2t motor overload protection has the objective of preventing damage to the motor and simultaneously operating it normally at its thermal limit. The function is only available when the motor controller is in closed loop operating mode (bit 0 of object 3202h set to "1") and the motor is not in profile torque mode or cycle synchronous torque mode. There is a single exception: If I2t is activated in open loop mode, the current is limited to the set nominal current even when the set maximum current is greater. This feature was implemented for safety reasons, so that it is also possible to switch out of closed loop mode and into open loop mode with a very high short-time maximum current without damaging the motor. Object entries The following objects affect I2t motor overload protection: 2031h: Peak Current - specifies the maximum current in mA. 203Bh:1h Nominal Current - specifies the nominal current in mA. 203Bh:2h Maximum Duration Of Peak Current - specifies the maximum time period of the maximum current in ms. The following objects indicate the actual state of I2t: 203Bh:3h Threshold - specifies the limit in mA, from which is determined whether switching is to the maximum current or nominal current. 203Bh:4h CalcValue - specifies the calculated value that is compared to the threshold in order to set the current. 203Bh:5h LimitedCurrent - shows the actual current value that was set by I2t. 203Bh:6h Status: Value = "0": I2t deactivated Value = "1": I2t activated Activation The three object entries above must have been appropriately specified to activate the mode. This means that the maximum current must be greater than the nominal current, and a time value must be entered for the maximum time of the maximum current. I2t operability remains deactivated when these conditions are not satisfied. Function of I2t A I2TLim is calculated by specifying the nominal current, maximum current, and maximum time period for the maximum current. The motor can run with maximum current until the calculated I2TLim is reached. The current is then immediately reduced to the nominal current. The following diagram again shows the interactions. In the first section t1, the current value is higher than the nominal current. At time t1Lim, I2tLim is reached and the current is limited to the nominal current. During the following time period t2, a current comes that corresponds to the maximum current. Accordingly, the value for I2tLim is reached faster than in time period t1.
I2t motor overload protection Description WARNING For stepper motors only the nominal current but no maximum current is specified. Therefore the usage of I2t with stepper motors is used at the users own risk I2t motor overload protection has the objective of preventing damage to the motor and simultaneously operating it normally at its thermal limit. The function is only available when the motor controller is in closed loop operating mode (bit 0 of object 3202h set to "1") and the motor is not in profile torque mode or cycle synchronous torque mode. There is a single exception: If I2t is activated in open loop mode, the current is limited to the set nominal current even when the set maximum current is greater. This feature was implemented for safety reasons, so that it is also possible to switch out of closed loop mode and into open loop mode with a very high short-time maximum current without damaging the motor. Object entries The following objects affect I2t motor overload protection: 2031h: Peak Current - specifies the maximum current in mA. 203Bh:1h Nominal Current - specifies the nominal current in mA. 203Bh:2h Maximum Duration Of Peak Current - specifies the maximum time period of the maximum current in ms. The following objects indicate the actual state of I2t: 203Bh:3h Threshold - specifies the limit in mA, from which is determined whether switching is to the maximum current or nominal current. 203Bh:4h CalcValue - specifies the calculated value that is compared to the threshold in order to set the current. 203Bh:5h LimitedCurrent - shows the actual current value that was set by I2t. 203Bh:6h Status: Value = "0": I2t deactivated Value = "1": I2t activated Activation The three object entries above must have been appropriately specified to activate the mode. This means that the maximum current must be greater than the nominal current, and a time value must be entered for the maximum time of the maximum current. I2t operability remains deactivated when these conditions are not satisfied. Function of I2t A I2TLim is calculated by specifying the nominal current, maximum current, and maximum time period for the maximum current. The motor can run with maximum current until the calculated I2TLim is reached. The current is then immediately reduced to the nominal current. The following diagram again shows the interactions. In the first section t1, the current value is higher than the nominal current. At time t1Lim, I2tLim is reached and the current is limited to the nominal current. During the following time period t2, a current comes that corresponds to the maximum current. Accordingly, the value for I2tLim is reached faster than in time period t1.
Description WARNING For stepper motors only the nominal current but no maximum current is specified. Therefore the usage of I2t with stepper motors is used at the users own risk I2t motor overload protection has the objective of preventing damage to the motor and simultaneously operating it normally at its thermal limit. The function is only available when the motor controller is in closed loop operating mode (bit 0 of object 3202h set to "1") and the motor is not in profile torque mode or cycle synchronous torque mode. There is a single exception: If I2t is activated in open loop mode, the current is limited to the set nominal current even when the set maximum current is greater. This feature was implemented for safety reasons, so that it is also possible to switch out of closed loop mode and into open loop mode with a very high short-time maximum current without damaging the motor.
Object entries The following objects affect I2t motor overload protection: 2031h: Peak Current - specifies the maximum current in mA. 203Bh:1h Nominal Current - specifies the nominal current in mA. 203Bh:2h Maximum Duration Of Peak Current - specifies the maximum time period of the maximum current in ms. The following objects indicate the actual state of I2t: 203Bh:3h Threshold - specifies the limit in mA, from which is determined whether switching is to the maximum current or nominal current. 203Bh:4h CalcValue - specifies the calculated value that is compared to the threshold in order to set the current. 203Bh:5h LimitedCurrent - shows the actual current value that was set by I2t. 203Bh:6h Status: Value = "0": I2t deactivated Value = "1": I2t activated
Activation The three object entries above must have been appropriately specified to activate the mode. This means that the maximum current must be greater than the nominal current, and a time value must be entered for the maximum time of the maximum current. I2t operability remains deactivated when these conditions are not satisfied.
Function of I2t A I2TLim is calculated by specifying the nominal current, maximum current, and maximum time period for the maximum current. The motor can run with maximum current until the calculated I2TLim is reached. The current is then immediately reduced to the nominal current. The following diagram again shows the interactions. In the first section t1, the current value is higher than the nominal current. At time t1Lim, I2tLim is reached and the current is limited to the nominal current. During the following time period t2, a current comes that corresponds to the maximum current. Accordingly, the value for I2tLim is reached faster than in time period t1.
