Recommendation for small relay board

Using Arduino Project Guidance
1

Hi there,
I'm currently trying to redo the wiring on my vintage motorcycle.
In order to reduce the cable mess from the seventies, I would like to use an Arduino Uno to keep the wiring harness as lean as possible.

Now, the Uno provides enough digital I/O for for this project however, I'm having trouble finding a good 8 channel relay board which is also pretty small.
Unfortunately, packaging is a real issue due to lack of real estate in the electrical component :confused:

All parts run on 12V and have a rather low power consumption. The only concerning item is the front light (12V/60W)

I was wonder if someone knows a relatively small relay board from a reputational brand : )

Cheers,
Tom

2

Hello tomjeyk
Take some time and ask the WWW for reed-relay.
Have a nice day and enjoy coding in C++.
Дайте миру шанс!

3

This is fraught with problems the electrical system on a vintage bike will not be well regulated and will be very noisy , possibly only half wave rectified .
I would restore the original wiring , I can’t see the need for an Arduino in the mix as the wiring logic is very simple .

You’ll also need a power supply for the Arduino and running the headlamp wiring through an Arduino based system could leave you with the light suddenly going off if the Arduino crashed.

Reed relays are not suitable

4

Or you could simply use a rack of independantly switched mosfets, take up very little space.
As above, don't see any need for an Arduino.

5

If you add an Uno, it is still a vintage motorcycle?

Even if you have to replace parts with new/modern parts, I would think you would want to use technology in keeping with the bike's era as much as is practical.

1 Like
6

Sorry for the late response.
Please correct me if I'm wrong, but would I not safe on space/weight on things like flasher relay, fuse box, etc?
Also the possibility of digital inputs can be helpful down the road. (e.g. using different instruments).

Lastly and out of curiosity, why are mosfets not a suitable solution for it?

Thanks again,
Tom

7

What ever you do had better include fuses.

PS. If you rely on those cheap hobby relays, expect to push you bike home.

8

Yes, but wouldn't just one instead of an entire fuse box be ok?

@Paul_KD7HB: Correct, that is the reason why I'm asking for a reputational brand recommendation

9

No , you need to fuse individual circuits . Still don’t get the motivation here , what you will end up with will be more complex and likely to be less reliable - all the circuits are simple and the Arduino has no calculations to do .
Battery > fuse> switch > relay ( if needed) > load .

Putting an Arduino in there adds an unnecessary level and what will it do ?

10

hmm could I not just use one fuse and place it between battery and all circuits?
Worst case, everything fails and not just the front/back light, but I don't think I really need to have my horn or speedometer light working when my front light is out..

A few reasons why I would like to use it:
Adding a "coming home" front light
Remove the bulky flasher relay
Use LED's for all signals and lights
Usage of single push button for signals
Adding an auto turn-off for signals
Adding function for hazard lights
Use any kind of single push button
Adding auto dimming for high beam

Now going back to the original question, someone recommended a mosfest board.
Doing research on it (sorry still a mechanical engineer), it seems to be the best way forward. Is there a recommendation for a good mosfet board?

Thanks,
Tom

11

This topic was automatically closed 180 days after the last reply. New replies are no longer allowed.