What do the automatic control instruments in the diagram represent?
Thread Content
What do the automatic control instruments in the diagram represent?
PG is the pump outlet pressure indicator, I is the motor current indicator, HS is the start/stop control; as for YA and YL, their functions are unknown – YA might be a motor alarm
1.PG, pump outlet pressure indicator； 2. I, interlock logic quantity; this diagram represents the logic quantity in the DCS ； 3.HS: Manual start/stop switch; this graphic represents a remote digital switch in the DCS ； 4.YA, event alarm – Y indicates an event; it seems to refer to a fault alarm here ； 5.YL, event indicator light; Y indicates an event, and it seems to be a fault status indicator light here.
See the reply on floor 3. Also, YA, fault alarm. YL, operating status. Generally, different design institutes have varying practices regarding the use of custom letters.