problem with state machine

[Turillo]

Hi! I've got a VI intended to control a storage tank. I've tried to do that by creating a simple state machine that changes the value(on/off) of some valves basing on 2 conditions:

-when a certain temperature reaches a pre-set value AND its derivative is <0, the state must change from on to off,

-when some time passes the state must change from off to on.

Unfortunately I can't get this work as it never changes state (e.g if I start with on always remain on "on" and viceversa).

Could you please tell me what I'm doing wrong? I'm attaching the screenshots of the 2 states.

Thanks!

[deceased · Accepted solution]

It looks like your shift regsiter might not be wired correctly.

[NeilR]

Hi Turillo

If you click the Cleanup Diagram button (little brush symbol) on the menubar you may be able to see better what's happening.

[Turillo]

Thank you all! I've solved my problem by both connecting the shift register as deceased connected and by connecting the enum control to the "if false" condition of the select block.