Rockwell-automation 1760-xxxx Pico GFX-70 Controllers User Manual Manual de usuario descargar pdf (Pagina 355)

1 Publication 1760-UM002B-EN-P - March 2005

Chapter

8

Inside Pico GFX-70

Pico GFX-70 Program Cycle

In conventional control systems, a relay or contactor control processes all the

circuit connections in parallel. The speed with which a contactor switches is

thus dependent on the components used, and ranges from 15 to 40 ms for

relay pick-up and drop-out.

With Pico GFX-70 the circuit diagram is processed with a microprocessor that

simulates the contacts and relays of the circuit concerned and thus processes

all switching operations considerably faster. Depending on its size, the Pico

GFX-70 circuit diagram is processed cyclically every 0.1 to 40 ms.

During this time, Pico GFX-70 passes through six segments in succession.

How Pico GFX-70 Evaluates the Circuit Diagram

In the first four segments Pico GFX-70 evaluates the contact fields in

succession. Pico GFX-70 checks whether contacts are switched in parallel or

in series and saves the switching states of all contact fields.

In the fifth segment, Pico GFX-70 assigns the new switching states to all the

coils in one pass.

The sixth segment is located outside of the circuit diagram. Pico GFX-70 uses

this to:

1 2 ... 350 351 352 353 354 355 356 357 358 359 360 ... 399 400

Comentarios a estos manuales

Sin comentarios