12V 2 channel relay  - Page 1
Forum section: electronics / projects

author: gsingh11
author_rank: Contributor
timestamp: February 03, 2023, 12:38:11 am
content: 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.

author: connectTek
author_rank: Regular Contributor
timestamp: February 03, 2023, 09:29:54 pm
content: 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

author: Zero999
author_rank: Super Contributor
timestamp: February 03, 2023, 10:23:01 pm
content: Quote from: gsingh11 on February 03, 2023, 12:38:11 amHow 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

author: gsingh11
author_rank: Contributor
timestamp: February 27, 2023, 01:06:25 pm
content: i can pay 100$ dollars if you help me to complete this project. Honestly I'm in need.

author: MarkS
author_rank: Unknown
timestamp: February 27, 2023, 08:12:22 pm
content: 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?

author: james_s
author_rank: Super Contributor
timestamp: February 27, 2023, 08:26:19 pm
content: 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.

author: gsingh11
author_rank: Contributor
timestamp: March 01, 2023, 11:56:46 pm
content: Quote from: james_s on February 27, 2023, 08:26:19 pmyeah i have everything in my mind i just need some help to put it togther

author: james_s
author_rank: Super Contributor
timestamp: March 02, 2023, 12:24:16 am
content: If you are not familiar with any EDA CAD package can you sketch a schematic on paper and post a picture of it?

author: gsingh11
author_rank: Contributor
timestamp: March 02, 2023, 12:31:02 am
content: Quote from: james_s on March 02, 2023, 12:24:16 ami have it.

author: james_s
author_rank: Super Contributor
timestamp: March 02, 2023, 12:32:06 am
content: 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?

author: gsingh11
author_rank: Contributor
timestamp: March 02, 2023, 12:33:52 am
content: Quote from: james_s on March 02, 2023, 12:32:06 amyes just problems in laying it down and i dont even know it works. i am getting trouble in the code too

author: thm_w
author_rank: Super Contributor
timestamp: March 02, 2023, 12:48:30 am
content: 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.

author: gsingh11
author_rank: Contributor
timestamp: March 02, 2023, 12:55:27 am
content: Quote from: thm_w on March 02, 2023, 12:48:30 amits the updated version of the same schematic

author: james_s
author_rank: Super Contributor
timestamp: March 02, 2023, 01:00:45 am
content: Quote from: gsingh11 on March 02, 2023, 12:33:52 amHave 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.

author: NiHaoMike
author_rank: Super Contributor
timestamp: March 02, 2023, 12:37:16 pm
content: It's probably not worth making a PCB for a one off, just buy some prototyping board and solder it.

author: james_s
author_rank: Super Contributor
timestamp: March 03, 2023, 01:53:34 am
content: Making a PCB is a good learning exercise though, gotta start somewhere, and this seems like a relatively easy beginner PCB project.

author: rfengg
author_rank: Regular Contributor
timestamp: March 03, 2023, 03:33:27 am
content: 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?

author: james_s
author_rank: Super Contributor
timestamp: March 03, 2023, 06:52:34 pm
content: Quote from: rfengg on March 03, 2023, 03:33:27 amYes D3 is clearly backwards. That's easily fixed though.

author: jonpaul
author_rank: Super Contributor
timestamp: March 04, 2023, 04:56:02 pm
content: buy a 12 v relay?

author: gsingh11
author_rank: Contributor
timestamp: March 07, 2023, 01:25:50 am
content: Quote from: james_s on March 03, 2023, 06:52:34 pmshould I use a MOSFET or relay as a switch to turn on my pump it is a 12V 3A water pump.

author: Algoma
author_rank: Frequent Contributor
timestamp: March 07, 2023, 03:23:48 am
content: 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%3DI 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.

author: james_s
author_rank: Super Contributor
timestamp: March 08, 2023, 02:43:30 am
content: Quote from: gsingh11 on March 07, 2023, 01:25:50 amEither one is perfectly acceptable.

author: Zero999
author_rank: Super Contributor
timestamp: March 08, 2023, 08:39:44 am
content: Quote from: gsingh11 on March 07, 2023, 01:25:50 amEither 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.