16 Channel Relay 12v or 5v?

Projects General Guidance
1

Hi guys,

I am planning on making a project with a 16 channel relay but looking online there are 5v and 12v modules. I am not sure which one would be better and really what the difference is other then the obvious working voltage difference.

I am planning on individually controlling led lighting on each step of the staircase (13 steps/13 relays needed)

Any help would be greatly appreciated.

Regards,
Kamil

2

Use logic level mosfets, not power-hungry noisy relays.

The advantage of a 16-channel module with 5volt relays is that it also can power the Arduino.
Because most (not all) of them have a 12>5volt buck converter fitted.
Post a link, so we can check.
Leo..

3

Wawa:
Use logic level mosfets, not power-hungry noisy relays.

The advantage of a 16-channel module with 5volt relays is that it also can power the Arduino.
Because most (not all) of them have a 12>5volt buck converter fitted.
Post a link, so we can check.
Leo..

SainSmart&reg 16-Channel 12V Relay Module for Arduino UNO MEGA R3 Mega2560 Duemilanove Nano Robot

The link is the schematic about SainSmart 16-Channel 12V Relay Module.

https://s3-ap-northeast-1.amazonaws.com/sain-amzn/20/20-018-103/16+relay+board.rar

Never heard of logic level mosfets before, not sure how they would work were as the relays seem easy enough to operate. Just bring the 12/24 power to the relay and back to led and then just send the signal from arduino to the relay board. But I will research about the logic level mosfets.

Thank you for your help Leo.

4

Yes, that relay board has the buck converter parts fitted (lower/left part of the board).
That board also has a serious design error. Opto couplers, but no opto isolation.
Not a big issue here, since it seems you're not going to use it to switch mains power.

A power fet can swith a LED strip directly.
Must be a logic level type, because of the low drive voltage (5volt) of an Arduino.
Use the first diagram on this page.
An other advantage of using mosfets is that fading in/out (dimming) is possible.
Can't do that with relays.

Another option is using addressable RGB LED strips. More expensive per meter, but you have full control over colour and brightness, and the whole stairs can be controlled with one Arduino pin.
A small Arduino, like a Nano, could be enough. And no other parts needed apart from a beefy 5volt supply.
Leo..

5

Wawa:
Yes, that relay board has the buck converter parts fitted (lower/left part of the board).
That board also has a serious design error. Opto couplers, but no opto isolation.
Not a big issue here, since it seems you're not going to use it to switch mains power.

A power fet can swith a LED strip directly.
Must be a logic level type, because of the low drive voltage (5volt) of an Arduino.
Use the first diagram on this page.
An other advantage of using mosfets is that fading in/out (dimming) is possible.
Can't do that with relays.

Another option is using addressable RGB LED strips. More expensive per meter, but you have full control over colour and brightness, and the whole stairs can be controlled with one Arduino pin.
A small Arduino, like a Nano, could be enough. And no other parts needed apart from a beefy 5volt supply.
Leo..

Thank you for a all the info. I will look into all of this once I get back home.

Just a quick question, does this board have the same error as the previous one?

Boladge 5V 16 Channels Relay Module Driver Board Module with Optocoupler for Arduino Raspberry Pi 51 AVR ARM PIC

6

Hi guys,

I am trying to light up each stair of my staircase separately with LED strip. I am planning on using the ultra-sonic sensors to control the led lights using relays.

I want to set it up that if you go up the stairs the ultra-sonic sensor will light up the steps one by one (1,2,3....13) and then leave all of them on for 10/20 sec. Then if you are going down the stairs the ultra-sonic sensor upstairs will light up the stairs the opposite way (13,12,11...1) and leave them on for 10/20 sec.

For that I will need a 16 channel relay module. I was planning on using https://www.amazon.co.uk/dp/B005WR747I/ref=psdc_430497031_t4_B06XKQQXKW but I was told that there is a "serious design error. Opto couplers, but no opto isolation." I was told that its "Not a big issue here, since it seems you're not going to use it to switch mains power."

  1. Could I possibly still use that board ?
  2. Is there a board that you could recommend or a different approach to this project.
  3. "Not a big issue here, since it seems you're not going to use it to switch mains power." Why would it be a issue if I was using the board to switch mains power ? Don`t really understand it.

Thanks for the help guys,
Kamil

7

Do you just plan to turn the lights on or off? No fading down when done, for instance?

What kind of LED strips are you using? I'd be using something like this: Adafruit NeoPixel Digital RGB LED Strip - White 60 LED [WHITE] : ID 1138 : $99.80 : Adafruit Industries, Unique & fun DIY electronics and kits No need for relays, AND you can do cool things like fading the LEDs on or off, light up in one color on the way up and another on the way down.

8

Same board, same error.
As said, it won't affect you if you're just switching low voltage LED strips.
Leo..

9

Why did you start a new thread for the same project.
Cross-posting is against forum rules.
Leo..

10

Sorry about that, I didn't know. I will delete this post if there is a way.

11

A moderator can merge the two threads.
Click the "Report to moderator" line (below every post), and ask.
Leo..

12

Wawa:
A moderator can merge the two threads.
Click the "Report to moderator" line (below every post), and ask.
Leo..

Did that, thanks Leo. Just a quick question when you said I would only have problems if I was using the relay for the main voltage, why is that? I was thinking of another project but instead of using led using main voltage lights. What would be my resolution for that, different board or using the other things you were talking about. Also if both of the boards how the same errors should I just go for the cheaper one?

13

8-channel relay boards have the option of using the extra layer of opto isolation.
16-channel relay boards don't have that option because of a design error.
You might not need opto isolation, but if you do, then just use two 8-channel boards.

I think most of these boards are made by the same factory in China.
A western retailer has the freedom to charge whatever is needed to sustain it's company.
If you order direct (ebay), then these 16-ch boards are about US$10, shipped to your door.
Remember what I said about the parts in the lower/left corner present/missing.
Leo..