71Initial Start UpVerifi cation of the encoder position following the P Lrn procedure.Friction and the inertial load of the cab and counter weights can lead to asmall error in the actual position value. The following procedure will verifywhether the position is correct or not.1) Set 0.LF.36 = to two times LF.17.2) Pick two floors in the middle of the shaft which are far enough apart suchthat the car reaches contract speed.3) Run the car between these floors and monitor LF.94 (peak phase current).Note the peak value for both the up and down run. The stored maximumvalue is cleared by pressing the down arrow. Make several runs toestablish the average value in each direction.4) Add 2000 to the value in LF.77 and run the car again between the sametwo floors. If the current value goes down then go to step 5. If the currentvalue goes up go to step 6.5) Add 2000 more to the value in LF.77 and run the car again. If the peakcurrent in LF.94 goes down further, add 2000 more and try again. Keepdoing this until the motor current begins to rise again. The value withthe lowest current is the best value. Jump to step 7.6) If the current went up initially, then lower LF.77 by 2000 and run the caragain. If the peak current in LF.94 goes down further, subtract 2000more and try again. Keep doing this until the motor current begins to riseagain. The value with the lowest current is the best value.7) Return the value of LF.77 to the value which gave the lowest current.Make note of this value in the job information for future reference.5.11.4 Absolute EncoderPosition Verification4) For high speed runs under load, it may be necessary to raise 0.LF.36 toa higher value. This value should not be set to a value higher than themotor manufacturer’s peak torque value, usually 2.0 to 2.4 times themotor’s rated torque.
