Originally Posted by
cheapfuel
Thanks Wileydog3 & yachno1: I now understand the flow.---- Regarding the switch itself, my little info book says it sourced from DC bus 1, with the valve being pneumatic. Maybe I am getting 'way over my head', but I am curious. Is the valve itself electrically moved into position, or does a solenoid open/close causing air to move the valve ?----Thanks again
You will often see 'electrically actuated-pneumatically operated' meaning the electrics allow the valve to operate and the pneumatics open it and keep it open. Let me check in some of my old manuals for a more precise explanation.
Some valves are electrically held open and some held closed. In the event of an electrical failure, some remain in the last commanded position, some fail open and some fail closed.
I'll get back to you... and good for you doing mental exercises. From what I understand, the brain is a mental muscle.. use it or lose it.