8.3 Precautions to Ensure Safe Tuning8.3.1 Torque Limit Settings8-58 Tuning8.3 Precautions to Ensure Safe TuningPerform the following settings in a way that is suitable for tuning.8.3.1 Torque Limit SettingsYou can limit the torque that is output by the Servomotor based on calculations of the torquerequired for machine operation. You can use torque limits to reduce the amount of shockapplied to the machine when problems occur, such as collisions or interference. If the torquelimit is lower than the torque that is required for operation, overshooting or vibration may occur.Refer to the following section for details.5.4.3 Torque Limit Selection on page 5-258.3.2 Setting the Position Deviation Overflow Alarm LevelThe position deviation overflow alarm is a protective function that is enabled when the SERVO-PACK is used in position control.If the alarm level is set to a suitable value, the SERVOPACK will detect excessive position devi-ation and will stop the Servomotor if the Servomotor operation does not agree with the refer-ence.The position deviation is the difference between the position reference value and the actualposition.You can calculate the position deviation from the position loop gain (Pn102) and the motorspeed with the following formula.Position Deviation Overflow Alarm Level (Pn520) [setting unit: reference units]*1. Refer to the following section for details.5.4.2 Electronic Gear Settings on page 5-23*2. When model following control (Pn140 = n.1) is enabled, use the setting of Pn141 (Model Following ControlGain) instead of the setting of Pn102 (Position Loop Gain).*3. The underlined coefficient “× (1.2 to 2)” adds a margin to prevent an A.D00 alarm (Position Deviation Overflow)from occurring too frequently.CAUTION Observe the following precautions when you perform tuning.• Do not touch the rotating parts of the motor during the SERVO ON state.• Before starting the Servomotor, make sure that an emergency stop can be performed at anytime.• Make sure that trial operation has been successfully performed without any problems.• Provide an appropriate stopping device on the machine to ensure safety.×60 Pn102 [0.1/s]/10*2 × Pn210Pn20EEncoder resolution*1Motor speed [min-1]Position deviation [reference units] =Pn520 > × ×60 Pn102 [0.1/s]/10*2 × Pn210Pn20E (1.2 to 2)*3Encoder resolution*1Maximum motor speed [min-1 ]