Yaskawa MP900 Series Ladder Programming Manual User Manual
Page 250

5.8 DDC Instructions
5.8.11 Linear Accelerator/Decelerator 1 (LAU)
5-181
Instructions
5
( 4 ) Additional Information
This information applies when the LAU instruction is used for integer or real number data.
[ a ] LAU Instruction with Integers
The LAU instruction for integers calculates the speed output value during acceleration, deceleration, and quick stops,
and the current acceleration or deceleration rates using the formula shown below based on predefined parameters.
In this formula, V is the speed output value, V’ is the previous speed output value, VI is the input value for the speed
reference, and Ts is the scan time set value.
Speed Output Value during Acceleration
The speed output value during acceleration is calculated as follows:
Speed Output Value during Deceleration
The speed output value during deceleration is calculated as follows:
Speed Output Value during a Quick Stop
The speed output value during a quick stop is calculated as follows:
Current Acceleration/Deceleration Rate
If DVDTF is ON, DVDT (current acceleration/deceleration rate) will be calculated according to the setting of DVDTS
(DVDT operation selection) using one of the following formulas. If DVDTF is OFF, DVDT is set to 0.
ARY (accelerating) turns ON when V’
≥ 0 and ADV > 0, or when V’ ≤ 0 and ADV < 0.
BRY (decelerating) turns ON at the following times:
• When V’ < 0 and BDV > 0, or when V’ > 0 and BDV < 0
• When V’ < 0 and QDV > 0, or when V’ > 0 and QDV < 0
LSP (zero speed) turns ON when V equals 0. EQU (equal) turns ON when VI equals V.
If RN (line running) is opened (OFF), the outputs for V, DVDT, and REM are set to 0.
ADV (acceleration rate) =
LV
× Ts (0.1 ms) + REM
AT (0.1 s)
× 1,000
If VI > V' (V' ≥ 0), then V = V' + ADV.
If VI < V' (V' ≤ 0), then V = V' − ADV.
If VI > V' (V' < 0), then V = V' + BDV.
If VI < V' (V' > 0), then V = V' − BDV.
BDV (deceleration rate) =
LV
× Ts (0.1 ms) + REM
BT (0.1 s)
× 1,000
If QS = OFF (VI > V', V' < 0), then V = V' + QDV.
If QS = OFF (VI < V', V' > 0), then V = V' − QDV.
QDV (Quick Stop Rate) =
LV
× Ts (0.1 ms) + REM
QT (0.1 s)
× 1,000
If DVDTS = ON, DVDT =
If DVDTS = ON, DVDT = (V – V')
× DVDTK
(V – V' )
× 5,000
ADV
INFO