12V 2 channel relay

[gsingh11]

Hi, I wanted to make 2 channel 12v relay for driving a solenoid valve and a water pump both 12V . I am looking for making a  schematic for it on kicad. can anyon help me with it.

[connectTek]

Jump in, have a go and then post your design. Then we can help. You can't run if you don't know how to walk.
All the best

[Zero999]

Hi, I wanted to make 2 channel 12v relay for driving a solenoid valve and a water pump both 12V . I am looking for making a  schematic for it on kicad. can anyon help me with it.

How much are you willing to pay?

You might get more help, if you kept it all to one thread, rather than creating a new one.
https://www.eevblog.com/forum/profile/?area=showposts;u=925435

[gsingh11]

i can pay 100$ dollars if you help me to complete this project. Honestly I'm in need.

[MarkS]

You should be able to drive both from one relay. Are you an electronics hobbyist having trouble, or someone looking for someone to do the work?

[james_s]

What part of the project are you stuck at? Do you have the schematic in your head and are having trouble drawing it up in KiCad? Or are you not sure how to wire up the relays? This seems like a good learning project.

[gsingh11]

What part of the project are you stuck at? Do you have the schematic in your head and are having trouble drawing it up in KiCad? Or are you not sure how to wire up the relays? This seems like a good learning project.

yeah i have everything in my mind i just need some help to put it togther

[james_s]

If you are not familiar with any EDA CAD package can you sketch a schematic on paper and post a picture of it?

[gsingh11]

If you are not familiar with any EDA CAD package can you sketch a schematic on paper and post a picture of it?

i have it.

[james_s]

It looks like you already have the complete schematic already in digital form, is it just laying out the PCB that you are stuck on?

[gsingh11]

It looks like you already have the complete schematic already in digital form, is it just laying out the PCB that you are stuck on?

yes just problems in laying it down and i dont even know it works. i am getting trouble in the code too

[thm_w]

The schematic is fine, but in the other thread you've posted another version for some reason: https://www.eevblog.com/forum/projects/faults-in-schematic/
Did you draw either of these?

How about post a screenshot of how you've laid out the components on the PCB in kicad.

[gsingh11]

The schematic is fine, but in the other thread you've posted another version for some reason: https://www.eevblog.com/forum/projects/faults-in-schematic/
Did you draw either of these?

How about post a screenshot of how you've laid out the components on the PCB in kicad.

its the updated version of the same schematic

[james_s]

yes just problems in laying it down and i dont even know it works. i am getting trouble in the code too

Have you tried watching a tutorial? It's not hard, but it does require a specific workflow. Draw the schematic, assign packages to the components, create a netlist, open that in pcbnew, place the components, draw the board outline, tidy up the placement and then start laying tracks. Use the widest track width that you can reasonably fit, especially for traces carrying a significant load.

[NiHaoMike]

It's probably not worth making a PCB for a one off, just buy some prototyping board and solder it.

[james_s]

Making a PCB is a good learning exercise though, gotta start somewhere, and this seems like a relatively easy beginner PCB project.

[rfengg]

Why is D3 wired to be forward biased when the relay is ON? This would shunt the current thru D3 rather than solenoid valve, right?

[james_s]

Why is D3 wired to be forward biased when the relay is ON? This would shunt the current thru D3 rather than solenoid valve, right?

Yes D3 is clearly backwards. That's easily fixed though.

[jonpaul]

buy a 12 v relay?

[gsingh11]

Why is D3 wired to be forward biased when the relay is ON? This would shunt the current thru D3 rather than solenoid valve, right?

Yes D3 is clearly backwards. That's easily fixed though.

should I use a MOSFET or relay as a switch to turn on my pump it is a 12V 3A water pump. 

[Algoma]

I like using these units from Sensata-Crydom, nice form factor for tucking away in small space, using standard Spade connectors: https://www.mouser.ca/ProductDetail/Crydom/ED06D5?qs=C7H2C2ytqFWMilA%252BuSOm4w%3D%3D

I had Installed a different model designed for 120VAC input in a condensate pump. Its saved the microswitch from carrying the motor's full load, Works flawlessly and fit perfect within the existing housing.

[james_s]

Why is D3 wired to be forward biased when the relay is ON? This would shunt the current thru D3 rather than solenoid valve, right?

Yes D3 is clearly backwards. That's easily fixed though.

should I use a MOSFET or relay as a switch to turn on my pump it is a 12V 3A water pump.

Either one is perfectly acceptable.

[Zero999]

Why is D3 wired to be forward biased when the relay is ON? This would shunt the current thru D3 rather than solenoid valve, right?

Yes D3 is clearly backwards. That's easily fixed though.

should I use a MOSFET or relay as a switch to turn on my pump it is a 12V 3A water pump.

Either can be used, but which is better suited, depends on the application.

A relay is more electrical robust, in that it won't be destroyed by moderate over-voltage and high current surges, but has a limited mechanical life. Frequency switching will cause rapid deterioration of the contacts.

A MOSFET, has no limit to the number or switching cycles, but is much more sensitive to electrical damage from electrostatic discharge and over-current.