One solenoid line doesn't work

[Danny Radius]

Dear Martyn,

I have already finishing assemble dc3 a month ago and it runs good with 1 valve. So I buy another valve. When I put the new valve on solenoid 2 port, the valve doesn’t work. When I push the start button, the green led is on, but the valve doesn’t open. I try to move the valve to another port (3 until 6) and the valve works well.
My friend which is a technician check the circuit using multimeter and found that the resistor 220 ohm and 10k ohm are shows different value (the resistor are broken).
Can you explain what is happening to the circuit, what cause the problem, how to prevent that problem and how to fix it.
Thank you in advance

Regards
Danny

[Martyn]

The circuit is very simple and shouldn’t cause any issues as long as things are connected correctly, especially the 220 ohm resistor which is (technically) not really required.

If you soldered the device it maybe you damaged the resistor when soldering (long shot).

Does the port work when the resistors are replaced?

edit: are the resistors the correct values?

[Danny Radius]

With your information that the 220 ohm resistor is technically not really required, I decided to check the mosfet. And I found the mosfet is short circuited. I think that is the problem. I will replace the mosfet right after it arrive and inform the result.
Thank you Martyn

Regards
Danny

[Danny Radius]

Dear Martyn,

It seems my problem is coming from the mosfet. After I replaced the mosfet, it runs well. I didn’t replace the resistor (220 and 10k ohm).
By the way, do you have any suggestion beside IRL540N and IRLZ44N that suitable for dropcontroller v3?
Thank you

Regards
Danny

[Martyn]

Glad you found the problem.

I have a list of logic level mosfets somewhere but cannot find it. Google “logic level mosfet” or “arduino mosfet”.

You want a mosfet with a low RDSon at 5V or below.

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