Wednesday, December 10, 2008

Relay board (plus a bit)


Following on from my successful 240V project, I designed a board to attach to the NGW100 and drive up to 8 relays.

The form factor for the board was dictated by the placement of the J5 and J6 jumpers on the NGW100, so there was a lot of spare board area.

So the logical thing to do was stuff in just about everything thing else I could think of that I ever interfaced to the NGW100. Which is why there's also 8-channel 1-wire interfaces, an SPI interface, and an RS-485 half-duplex driver.

The silk screen lists the RS-485 driver as the MAX-487, but it's really the equivilant 3.3V part. (I got lazy and skipped making a custom part in the library for it).

This board will plug straight into the NGW100, picking up all the signals from J5 and J6, and picking up supply power for the relays from J15, being the pre-DC/DC voltage.

This means that I can supply the NGW100 with 12VDC, which the onboard dc-dc convertor will drop down to 3.3V for the ARM32, and the daughterboard will take directly as 12VDC for the relay driving, but 3.3V for the SPI, 1-wire, and RS485.
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10 comments:

Anonymous said...

Hi,

It is exactly about what I need to control my home environment. Would you be able to share your project details with me? Please, answer to dimia[at]mail[dot]ru.

Thanks in adnvance!

Dimi

Michael said...

Sure. What would you like to know about it?

Anonymous said...

I also have ngw100 board and would like to remotely control/monitor my home environment: heating system, lights etc.
I would appreciate if you forward me your relay board schematics and pcb design in some usable format. pdf for schematic and component list is good enough. But I am not sure what will be the "right" format for the pcb drawings. I will have to order pcb from some company as you did.
Next is software part. You mentioned that you developed some library routines to control this hardware. That is another point of interest.
To summarize - I want to replicate your "relay board" project: 1) access to rs-485 bus (Danfos heating controller); 2) read 2-3 1-wire temperature sensors; 3) control the relays.
Regards, Dimi.

Anonymous said...

Hi Michael,

Did I ask something wrong? Do I want too much?
I understand that you spent a lot of efforts doing this project. I am ready to compensate. I am not going to use this for any commercial projects, just for personal use at at home.
You should better say no, but don't just ignore me. Thanks!

Dimi

Michael said...

My apoloiges; I just forgot about this. I'll upload the eagle files shortly.

Anonymous said...

Thanks, Michael! You can either upload these files or email me dimia[at]mail[dot]ru. Do you use some "standard" library functions to control the relays and read the sensors? If so, could you give the reference to that library, please?

Thanks and regards,
Dimi

Anonymous said...

Hi Michael,

Please, do!

Regards,
Dimi

Anonymous said...

Michael,
Upload the Eagle files for your "relay board", please.

Dimi

marius said...

hi,

i'm interested in this project for the control of temperature and humidity in a room.

Can you please give me more details on it.

caldura(at)hotmail(dot)com

Winston said...

Michael,

I'm also very interested in your relay board for a home project. Please, please could you get in touch with me.

Many thanks in advance!