I have a 12V 2 motor agriculture spray pump and a 12 V solenoid valve. I need to know which flyback diode to use, and how to make the choice. I have been told that the transients are very short lived when the pump switches off, something like 8 ms, but the current can be very high. In my inventory I have 1N4007, 1N5822 3 A, and SB580 5 A diodes. What should be my choice? The latter 2 seem too expensive for electronics stuff, almost 70 times the cost of an 1N4007.
EDIT 1 :
There is another problem with regards this project which I need help with.
So my Diaphragm pump has the below basic specifications
Twin motor unit.12V 5-8 Amps requirement.Peak rush current - not known.
Since the peak rush current is not known, when I was using it with the 12V 16 Amps SMPS power supply, sometimes the SMPS would shut down, which I guess was because of the rush current being higher than the rated capacity of the SMPS. So I got myself a 30 Amps SMPS.
But I have been told that the smarter thing to do still was to soft start the twin motors as we don't know how high the rush current can be. (And I might save some money going back to the 16 Amps power supply from the 30 Amps power supply).
I have never made a soft start circuit, so I searched the internet and came across this, but this is for a different motor.
Can this circuit soft start my pump reliably without eventually failing?
I understand that the flyback diode needs study based on @winny's comment, but are the other components suitable?