Maximum overload current of the inverter

For the purpose of current limitation, a maximum overload current can be set for the inverter. If the current consumption of the motor exceeds this current limit, the inverter changes its dynamic behaviour, in order to counteract this exceedance.

Details

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The maximum current of the inverter can be set in 0x6073 (P324.00).

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Reference for the percentage setting of the maximum overload current is the rated motor current set in 0x6075 (P323.00).

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The actual motor current is displayed in 0x2D88 (P104.00).

If the change in the dynamic behavior carried out by the inverter does not result in exiting the overcurrent state, the inverter outputs an error.

If 0x6078 (P103.00) (actual value in %) exceeds 0x6073 (P324.00) (max. actual value in %), a message 0x238A is displayed. The status is also indicated in the following network status word bits:

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0x400C:001 bit 14

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0x400C:002 bit 2

Load response	Impact
Overload during acceleration in motor mode	A longer time than is required for reaching the frequency setpoint is set.
Overload during deceleration in generator mode	A longer time than is required for reaching standstill is set.
Increasing load at constant frequency	If the motor current limit value is reached: – The inverter reduces the effective speed setpoint until a stable working point is set or an effective speed setpoint of 0 rpm is reached. – If the load is reduced, the inverter increases the effective speed setpoint until the setpoint speed is reached or the load reaches the current limit value again.
	When the generator current limit value is reached: – The inverter increases the effective speed setpoint until a stable working point is reached or up to the maximum permissible output frequency 0x2916 (P211.00). – If the load is reduced, the inverter reduces the effective speed setpoint until the setpoint speed is reached or the load reaches the current limit value again.
	If an abrupt load is building at the motor shaft (e.g. drive is blocked), the overcurrent switch-off function may respond.

Example: Overcurrent switch-off in case of a sudden load at the motor shaft

Parameter

Address	Name / setting range / [default setting]		Information
0x6073 (P324.00)	Max. current (Max. current) 0.0 ... [200.0] ... 3000.0 %		Max. current of the inverter. – 100 % = Rated motor current (0x6075 (P323.00)) – If the current consumption of the motor exceeds this current limit, the inverter changes its dynamic behaviour in order to counteract this exceedance. – If the modified dynamic behaviour fails to eliminate the excess current consumption, the inverter outputs an error. When 0x6078 (P103.00) (current actual value in %) exceeds 0x6073 (P324.00) (max. current actual value in %) the message 0x238A is displayed. This status is also displayed in the following network status word bits: – 0x400C:001 bit 14 – 0x400C:002 bit 2 Note! This parameter is not identical to the ultimate motor current I_ULT. – The value set in 0x2D46:001 (P353.01) (Threshold) is a limit value for synchronous motors to protect their magnets. – The value to be set here should always be considerably below the ultimate motor current.