Example Program for ALPHA Series

3. Ventilation Control of Greenhouse: Case 1

 

 

In this example ventilation fans are operated to regulate the density of carbon dioxide gas or warmth in a greenhouse. The ALPHA series' Hour Meter is used to control the ventilation fans in a long cycle period.

The second fan is controlled via a Delay Timer which sets a certain time difference between the starting time of the two fans.

Contents of Control:

  1. When the automatic mode button (S1) is pressed, the automatic operation of the ventilation fans starts. The cycle of one-hour operation and one-and-a-half-hour recess is repeated until the stop automatic mode button (S2) is pressed.
  2. When the manual mode ON/OFF button (S3) is pressed during the automatic operation, manual mode is entered. The fans operate according to the status of the button (S3).
  3. When the manual mode ON/OFF button (S3) is set to ON, the fans rotate, and when it is set to OFF, the fans stop.
  4. Fan 2 starts 30 seconds after fan 1 has started.

Installing and Wiring:

Refer to the ALPHA/ALPHA2 Hardware Manuals for correct installation and wiring procedures.

Program:

Refer to the ALPHA/ALPHA2 Programming Manuals for explanations concerning function blocks and program input. Refer to the a Software Manual when using the AL-PCS/WIN-E programming software.