15. Handy Instruction Design Examples In this program, the scan cycle is fixed as 20ms and the scan times of RAMP instruction are 100. Therefore the ramp duration is 2s. z When the button Up is pressed (M0 = ON), the crane will perform gradual start to lift goods and the voltage output will increase from 0 to 10V in 2s. When the crane reaches the target height, operator can press the button Stop (M2 = ON) to execute gradual stop. The voltage output will decrease from 10 to 0V in 2s. The process is as follows: X0 M0 X2 M2 Gradual start Gradual stop (10V) 2000 0 (0V) M1029 z The goods landing process also requires the same ramp up (gradual start) and ramp down (gradual stop) duration.
z The frequency of AC motor drive is in proportion to the output voltage of PLC. For example, the frequency of Delta VFD-M series AC motor drive varies from 0 to 60Hz while the output voltage of DVP10SX varies from 0 to 10V. In addition, the motor rotation speed is in proportion to the frequency of drive. Therefore, gradual start and gradual stop can be performed by controlling the variation of output voltage on DVP10SX. DVP-PLC Application Examples 15-5 can times: 100 Scan times:10 0