Shihlin SDH Series, Manual

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SDH Series Manual
4 electronic gear numerators are available for users to select. Enable the function CM1 and CM2 of DI to switch. See the
table below.
Name CM1 CM2 Control mode
Electronic gear numerator 1 (PA 06) 0 0
Pt、Pr
Electronic gear numerator 2 (PC 32) 1 0 Pt、Pr
Electronic gear numerator 3 (PC 33) 0 1 Pt、Pr
Electronic gear numerator 4 (PC 34) 1 1
Pt、Pr
0: OFF(CMx-SG is open-circuit), 1:ON(CMx-SG is short-circuit), x=1,2
Calculation of electronic gear ratio:
Before calculating the value, users have to know the specifications such as the resolution of motor encoder (22bit Pulse/
rev), the deceleration rate, and the gear ratio of the machine. Use the following equation to calculate the electronic gear
ratio.
If a gear ratio between motor and loads existed, to multiply the factor :
The following example explains the method for setting the electronic gear ratio.
Load distance per revolution is 1mm, the resolution of motor encoder is 22-bitPulse/rev, the gear ratio of load mechanism
to motor shaft is 1, if the demand distance is 5μm, the calculation is listed below.
=1048576/200
From above, it could be known that by setting the electronic gear numerator as 4194304 and the electronic gear
denominator as 200, then the ball screw rod would be shift a 5-μm distance after a position pulse command.
6.4.5 Torque limit of position control mode
See section 6.3.4. for details.
6.4.6 Position loop gain
If users need to use manual-gain tuning for position loop, to set parameters of speed loop (see Section 6.3.5) is
priority since position loop is outside control of speed loop. Then users could set proportion gain and feed-forward gain of
position loop. Usually, position gain is 1/4~1/6 value of the speed loop gain. Users could also use auto-gain tuning mode
to set the gains of position and speed loop automatically. Position loop block diagram is presented below.