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Re: Vacuum pump issues
Posted: Fri Nov 13, 2015 2:00 pm
by android
Hi ,my FET switch broken. I replaced it with another 55NF06 . But it looks like my FET is in good condition. But not working with my tinyG. i also replaced my valve.
The problem is when i give run job my FET switches but its not coming back to off condition.
Re: Vacuum pump issues
Posted: Fri Nov 13, 2015 2:37 pm
by mrandt
android wrote:The problem is when i give run job my FET switches but its not coming back to off condition.
Suggest you add a resistor from gate (control pin) to ground to help discharge FET gate if TinyG pin is inactive. 10k should probably work.
Re: Vacuum pump issues
Posted: Fri Nov 13, 2015 7:20 pm
by mucek
... And a reverse polarity protection diode over MOSFET D-S ...
Toys with motors, not to mention solenoid (which is pure coil
) make nasty back currents when switched off, which can simply blow MOSFET. Most MOSFETs have a protection diode built in, but in many cases it is not strong enough to protect MOSFET.
Regards,
Gregor