Powering solenoids directly through breadboard

I am trying to power two 12V solenoids directly through the breadboard instead of going through VIN on the arduino. I am using a variable voltage power supply (3V-24V) with a female DC power adapter (jack to screw terminal block) and jumper wires from the adapter to the breadboard. I am unsure why this setup does not work. When I plug the power supply into the jack on the arduino and connect the breadboard to VIN and GND using jumper wires, the solenoids work perfectly. It does not make sense to me why going through the arduino works, but when bypassing the arduino and sticking the jumper wires directly into the breadboard the solenoids do not work.

I have tested the jack to screw terminal block adapter by setting up a simple circuit on the breadboard with an LED so I know that the problem is not with the adapter. Also, given that the solenoids work when connected to power via VIN, I don't think the issue is with the circuit I have set up either.

So, if the power supply, the jack to screw terminal block adapter, and the circuit are all working, then what could the issue be?

Clear photos, wiring diagram or schematic, links to ancillary parts (power supply, relays etc)
Then we can talk.

Thanks for the response!

First up, here is the wiring diagram for the set up where the solenoids actually function.

In this situation, there is also a 12V power supply connected to the jack on the arduino.

Since I am a new user my replies cannot contain more than one picture and no more thank two links so I will have to submit multiple replies to show everything. I apologize in advance.

Next, here is the wiring diagram for the setup where the solenoids fail to do anything.

Also, I used a battery to symbolize the power supply. So where you see the battery is actually a 12V power supply with a female DC power adapter (jack to screw terminal block). The power supply is this one set to 12V.

In both diagrams, the components are as follows:

Again I'm sorry for the many replies. Please let me know if any other information would be helpful!

ok, the first thing that jumps to my eye is the solenoid -V rail doesn’t seem to be common with the Arduino GND rail…

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That is not a wiring diagram, or a schematic. It's s jumble of disconnected components on a page. This is what you see if you construct a circuit in Fritzing's "Breadboard View" , then switch to "Schematic View" but then do not finish the job.

The dotted lines indicate connections that Fritzing thinks you need to draw, based on the Breadboard view connections. So please finish drawing the schematics. Arrange the components and draw the connections to make it neat and easy to follow, with minimum wires crossing each other.

Remember, in a schematic, the placement of components does not need to reflect their physical layout. Only the connections, and the clarity of the schematic, are important.

Yep, that was the issue. It's painfully obvious now...

Thank you for pointing that out! It is working perfectly :slight_smile:

Thank you for this feedback Paul. I had no idea that the dotted lines were suggestions by fritzing. I just assumed that that's how schematics were supposed to look. I am very very new at this, but learning more everyday!

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