120External Load WeigherPre-torque gainA car weighing system can be used to provide an analog signalto the elevator drive which is proportional to the load in the cabin.When LF.30 is set to 3, this analog signal is used to generate anexact counter torque to hold the car stationary when the brake isreleased. This is important for gearless speed control applications.- 10 V the car is empty negative rated torque0 V car weight + half load= counterweight 010 V the car is full positive rated torqueIf the rated torque is too small or too large , it can be increased ordecreased with LF.67.Unit: -Value range: 0.25 … 2.00Default setting: 1Adjusted value: depends on the required torqueExternal Load WeigherPre-torque offsetIf the counter weight is not 50 % (cabin weight + 50% of max. load),the pre-torque can be adjusted with LF.68.Unit: %Value range: – 100.0 % … 100.0 %Default setting: 0 %Adjusted value: depends on the counter weightExternal Load WeigherPre-torque directionThis parameter can be used to invert the direction of the pretorquebeing applied to the motor.Unit: 1Value range: 0 => +10V = positive torque1 => -10v = positive torqueDefault setting: 1Adjusted value: depends on the required torque directionParameter Descriptioni Note: Parameters LF.67-69 refer to pre-torque using an externalpre-torque device (load weigher), not the drive synthetic pre-torque function. When using a load wither, LF.30 can be set to 3to activate pre-torque.
