Instructions for Using Position Mode

According to the position instructions of the upper computer (such as pulse input) or the internal position instructions of the servo, the main steps for position control are as follows:

Figure 5-1 position mode set diagram

position mode wiring

• Precautions：
• Signal cables and power cables must be wired separately, with a minimum distance of 30cm between them；
• When connecting signal cables due to insufficient length, the shielding layer must be reliably connected and grounded;
• +5V is referenced to GND, and+24V is referenced to COM -. Do not exceed the maximum allowable current, otherwise the driver will not function properly.

Function code settings related to position control mode

Parameter settings in position control mode, including mode selection, command pulse form, electronic gear ratio, DI/DO, etc.。

1. Position command input settings
2. Position instruction source

Set function code P05-15, specify position command source

1. Position command direction switching

By setting the DI function FunIN.27, it is possible to use DI to control the direction switching of position commands, meeting the needs of direction switching

1. Pulse command form

Set function code P05-16 and select the form of external pulse command, including "direction+pulse", "orthogonal pulse", and "CW+CCW"。

Function code P05-17 can be set to reverse the instruction pulse signal. For example, in the "direction+pulse" mode, a value of 0 indicates positive logic, and a value of 3 indicates negative logic.

The principles of the three types of pulse command forms are shown in the table below

1. Selection of instruction pulse filter

Select the appropriate pulse filter based on the frequency of the highest pulse, which can be set through parameter P05-18. If choosing an inappropriate filter may result in the loss or increase of pulses received by the servo unit.

1. Pulse input prohibited

Disable pulse command input by setting DI function FunIN.13。

1. Electronic gear ratio setting

Set the electronic gear ratio according to the actual situation.

The principle of electronic gear ratio is shown in the following figure

Figure 5-3 Principle diagram of electronic gear ratio action

When P05-00=0:：

The motor and load are connected through a reduction gear. Assuming that the reduction ratio between the motor shaft and mechanical load shaft is n/m (the electric shaft rotates m turns and the load shaft rotates n turns), the calculation formula for the electronic gear ratio is as follows：

The R8 servo supports up to 2 sets of electronic gear ratios and can use the gear ratio switching function (FunIN. 24) to complete gear ratio selection

When P05-00 ≠ 0：

At this time, the gear ratio is not related to P05-02, P05-04, P05-06, P05-08,and the gear ratio switching function is invalid.

1. Position instruction filtering setting

The position command smoothing function refers to filtering the input position command to make the rotation of the servo motor smoother. This function has a significant effect in the following situations

• • The output pulse command of the controller device has not undergone acceleration/deceleration processing, and the acceleration/deceleration speed is very high；
  • The instruction pulse frequency is too low；
  • The electronic gear ratio is more than 10 times。

Note: This function has no effect on the displacement (total number of position commands).

The settings for the parameters related to the position command smoothing function are as follows

When the value is set to 0, the filter becomes invalid.

1. Position deviation clearing function

By setting the DI function FunIN.35, DI can be used to control whether to reset the position deviation.

1. Frequency division output function

The servo pulse output source is selected by P05-25, and the pulse command synchronous output function is generally used in synchronous control situations

By setting P05-32, the pulse output signal type can be selected.

By setting P05-30, the servo driver will divide the frequency according to the set value and output it through the frequency division output port . The P05-30 set value corresponds to the number of pulse outputs。

For example, when the pulse output signal type is selected as 0 (AB phase, 4x frequency), the motor rotates once, and A/B phases output P05-30 pulses orthogonally。

The phase shape of the output pulse feedback can be adjusted through P05-26

The parameters related to single-phase output OZ signal are configured as follows:：

Adjust the effective current level of Z-pulse output by P5-27

Adjust the Z-pulse dead time through P05-39

Adjust the pulse width of Z signal by P05-76