Controlling 500 relays

[davidwenzl]

Im pretty new to programming and figuring out what i need for hardware. I need the ability to control up to 500 relays independently of each other. Any help or advice would be greatly appreciated. Thank you

[lastchancename]

How are the relays located wrt each other?
Whats the larger scope of your project ?

Photos or drawings might help.

[LarryD]

• What do these relays control ?

• Always show us a good schematic of your proposed circuit.
  Give links to components.

[gilshultz]

@davidwenzl

Any help or advice would be greatly appreciated

Interesting project but we are not a free design or code writing service. We will be happy help out with your design and or code but first you have to make a reasonable attempt to design it, write it, post it and explain what is not working properly.

If there is hardware such as your relays and Arduino it is always best to post links to technical information as there are many versions of the same or different items. Relays come in many sizes, types, voltages, etc. What environment will they be in? How far apart do they need to be? What is the speed requirement? How fast do you have to cycle the relays? Will more then one relay be on at a time and other applicable information.

Since we cannot see your project you need to post a preliminary schematic using the language of electronics, an annotated schematic, (best) or a clear picture of a drawing. Pictures never hurt. Frizzing diagrams are not considered schematics here, they are wiring diagrams.

[Paul_KD7HB]

@davidwenzl

I need the ability to control up to 500 relays independently of each other.

Does your design also require feedback from the relay to ensure it did in fact operate? Is any type of safety protocol needed?

[Ron_Blain]

This would go much better if you fully define the project. You mention 500 relays but no mention of relay coil voltage or current? Less details you aren't going to get much help.

Ron

[zwieblum]

Might be that you have to reconsider your design ...

[Grumpy_Mike]

@davidwenzl

I need the ability to control up to 500 relays independently of each other.

Scaling up a project always brings its own difficulties. This is because things that normally are minor or secondary effects become major difficult and matter a lot. As you have no experience to fall back on, then sorry but you don't stand a chance.

Also it is one thing controlling the relays themselves, but quite another dealing with the effects of 500 loads being switched. So at the moment this is just a pipe dream.

There is so much you have not told us, in fact you have told us very little of use yet. Like at what distance are these relays from the Arduino?
What Arduino would you like to use?
What is the nature of these loads, and what relays you are planning to use?
Just what are you trying to do?

I would advise you to start with just 10 relays and see how this goes. Five hundred of anything is going to be very expensive.

[DVDdoug]

With serial addressing you can control an almost unlimited number of on/off devices.

500 regular electro-mechanical relays is a lot, and the coils are going to require a lot of energy, depending on how many are powered-on at one time. ...Plus the energy for whatever the relays are controlling.

There may be a solid-state alternative depending on what you're trying to control.

It's also a lot of soldering!

[xfpd]

@DVDdoug

control an almost unlimited number of on/off

Here is an example of 32 relays with 4 muxes. Add 58 more muxes.

sprinklers - Wokwi ESP32, STM32, Arduino Simulator

[sterretje]

@xfpd

with 4 muxes

That's not with muxes

[paulpaulson]

@davidwenzl

Any help or advice would be greatly appreciated. Thank you

Hello davidwenzl

Welcome to the best Arduino forum ever.

The first thing I would recommend is to create a scalable system design.

I am thinking of considering different Arduino controllers in the system development, which provide different numbers of I/O pins and thus represent a control unit.

Another point would be to develop a good programme to control the outputs on the control units.

There is still a lot to do.

[noiasca]

@davidwenzl

I need the ability to control up to 500 relays independently of each other.

Try this order:

1. Start with one relay. Make your sketch doing exactly what you need with this single relay.
2. Learn about arrays
3. Implement as many relays as long as you have enough memory

[PerryBebbington]

Political comments removed.
Please stick to helping the OP.

Thank you.

[TomGeorge]

Hi, @davidwenzl
Welcome to the forum.

How to get the best out of this forum

See also FAQ - Arduino Forum for general rules on forum behavior and etiquette. Hello, Welcome to the Arduino Forum. This guide explains how to get the best out of this forum. Please read and follow the instructions below. Being new here you might think this is having rules for the sake of rules, but that is not the case. If you don’t follow the guidelines all that happens is there is a long exchange of posts while we try to get you to tell us what we need in order to help you, which is frus…

Can you please describe your project?
When you control these 500 relays, what criteria determines which relays are on and which are off?
What is the input data.

If we know your project better, we can offer solutions better adapted to your project.

Can you please post a link to data/specs of our relays?

Thanks.. Tom..

[xfpd]

@sterretje

That's not with muxes

Yes, it is. (without context)

[sterretje]

@xfpd, you'll have to give the context because I have no idea what you're talking about.

[xfpd]

@sterretje

you'll have to give the context

I did.