Hi,
I try to control some heating systems which have three-way valves for the heating water temperature control. On the hot water inlet of the valve enter the water from a puffer tank , which can have 85 gr C, on the cold inlet comes the return from the heating system.
The valve have a small (3 Watt) engine.
I used PLEG for control the valves: while the mixed water’s temperature is < 55 gr C, the shutter have to make a short (5 sec) move to up, and when the water’s temperature is > 60C, the shutter makes short moves (5 sec) down. In this way, the shutter makes a lot of very short moves.
The problem is, that after 8-10 commands, the shutter loses his position and the UI indicates 50%, at any position of the shutter.
Any advice?