What you have said is what I thought, but now it's completely clear. Thank you.
I'm not sure what configuration you have I'm going to leave the solenoid configuration for the moment and ask about plan B (or was it A) .
Plan B was to to feed 36 v in, perhaps turning down current. I'm sure we have XS current (because I know of an injector test rig which operates at about 5 amp but doesn't need to open and close as fast as we need). We can run at 15 amp.
We argued about this, current and voltage, and you have introduced an additional idea. To explain our argument, because the valve needs to open too fast to let the bleed drop the pressure, I said we needed high voltage to build a quick current (The Man estimated the inductance is only about 2.5 uH . So he couldn't believe we needed more voltage. But at 12.5 v it rarely worked at all while at 18 v it was reliable in test mode).
But now (since your remarks) we are wondering if it's opening OK but not shutting fast enough. Possibly big-step-forward.
Now will this help? Plan B: apply 36 v to the current generator. Put a 10 amp fuse in to the lead to the solenoid. Protect the timer circuit by taking the 36 v rail, and between that rail and the 7812, putting a 2.5 resistor (0.5W) and then the Zener diode (10 v 1.5 W) and then the 7812 with its two caps. Then the ic 4013.
Question: is that OK?
Now, the current in the solenoid will collapse faster. But I'd better wind back the applied current, I suspect. So, second Question: is that right?
This has avoided using the kick-back idea to generate voltage which might lead me to do something beyond my understanding. The thing at present works remarkably but not perfectly so it's best to alter things the least.
Malc
I suspect
I'm not sure what configuration you have I'm going to leave the solenoid configuration for the moment and ask about plan B (or was it A) .
Plan B was to to feed 36 v in, perhaps turning down current. I'm sure we have XS current (because I know of an injector test rig which operates at about 5 amp but doesn't need to open and close as fast as we need). We can run at 15 amp.
We argued about this, current and voltage, and you have introduced an additional idea. To explain our argument, because the valve needs to open too fast to let the bleed drop the pressure, I said we needed high voltage to build a quick current (The Man estimated the inductance is only about 2.5 uH . So he couldn't believe we needed more voltage. But at 12.5 v it rarely worked at all while at 18 v it was reliable in test mode).
But now (since your remarks) we are wondering if it's opening OK but not shutting fast enough. Possibly big-step-forward.
Now will this help? Plan B: apply 36 v to the current generator. Put a 10 amp fuse in to the lead to the solenoid. Protect the timer circuit by taking the 36 v rail, and between that rail and the 7812, putting a 2.5 resistor (0.5W) and then the Zener diode (10 v 1.5 W) and then the 7812 with its two caps. Then the ic 4013.
Question: is that OK?
Now, the current in the solenoid will collapse faster. But I'd better wind back the applied current, I suspect. So, second Question: is that right?
This has avoided using the kick-back idea to generate voltage which might lead me to do something beyond my understanding. The thing at present works remarkably but not perfectly so it's best to alter things the least.
Malc
I suspect