|
SimonHa
|
 |
« on: December 31, 2010, 03:42:26 PM » |
|
Has anyone come across a small module/kit that controls only 1 or 2 relays (via a DS2408 presumably) on a 1-wire network? This topic comes up in passing here:
http://www.navitron.org.uk/forum/index.php/topic,11793.msg128966.html#msg128966 but I thought it might justify a discussion of its own as I suspect most of us have 1-wire networks for temperature monitoring. E.g.: *perhaps a DS2408 could be soldered onto the side of this but it would be better on the PCB Note I already have a Hobby Boards 8-relay unit ( http://www.hobby-boards.com/catalog/product_info.php?cPath=24&products_id=1554) - I'm very pleased with it, but it costs around $80 including postage and is overkill if you just want to switch one or two appliances. Ideally I think I'd like a plug in appliance module that was self contained, possibly taking relay power from a 12V aux supply on the 1-wire network to keep it simple/cheap. Note I'm reluctant to introduce an X10 interface too - I was hoping to keep things "simple"  |
|
|
|
|
Logged
|
|
|
|
|
StBarnabas
|
|
« Reply #1 on: January 01, 2011, 09:04:47 AM » |
|
I have used Eric's DS2405 PIC clone but only switch on and off LEDs. You would also need a relay as these are only TTL levels.
Sean
|
|
|
|
|
Logged
|
 Gestis Censere. 40x47mm DHW with TDC3. 3kW ASHP, 9kW GSHP, 3kW Navitron PV with Platinum 3100S GTI, 6.5kW WBS, 5 chickens. FMY 2009. |
|
|
|
ericw
|
|
« Reply #2 on: January 01, 2011, 10:18:01 AM » |
|
Simon, I haven't come across a 1 wire dual relay board. If one does not surface then I would suggest 1 of 2 options. Electrically the best one would be to remove the mosfets from the relay board you have suggested, and replace then with a DS2413. However the DS2413 is available only as a surface mount device so you would need to solder it to a daughter board such as ( http://iteadstudio.com/store/index.php?main_page=product_info&cPath=10_12&products_id=69) and then wire it in. Alternatively I could do you a HalfBee which would look like a DS2413 but have inverted outputs so it could drive the relay board. This is a DIL device and can be mounted on a scrap of Veroboard connected in series with the input terminals of an unmodified board. Eric |
|
|
|
|
Logged
|
|
|
|
|
SimonHa
|
|
« Reply #3 on: January 01, 2011, 10:42:59 AM » |
|
Simon, I haven't come across a 1 wire dual relay board. If one does not surface then I would suggest 1 of 2 options. Electrically the best one would be to remove the mosfets from the relay board you have suggested, and replace then with a DS2413. However the DS2413 is available only as a surface mount device so you would need to solder it to a daughter board such as ( http://iteadstudio.com/store/index.php?main_page=product_info&cPath=10_12&products_id=69) and then wire it in. Alternatively I could do you a HalfBee which would look like a DS2413 but have inverted outputs so it could drive the relay board. This is a DIL device and can be mounted on a scrap of Veroboard connected in series with the input terminals of an unmodified board. Eric Thanks for the updates StB & Eric. I'm not really an electronics person and have never soldered surface-mount components - is it difficult since they're presumably designed to be attached by machine? Also what does "PIC" mean as I've seen it mentioned elsewhere too? I forgot to mention that I had come across this article: http://electronicdesign.com/article/components/drive-a-relay-using-a-1-wire-addressable-switch725.aspx (and circuit diagram http://archive.electronicdesign.com/files/29/7258/figure_01.gif). What's puzzling me is why this isn't more common as it seems an obvious requirement to me - am I missing something? Perhaps most HA is for lighting control and so everyone has X10, C-Bus or whatever for that already. Simon |
|
|
|
|
Logged
|
|
|
|
|
|
|
|
|
wyleu
Guest
|
|
« Reply #6 on: January 01, 2011, 01:11:21 PM » |
|
Not cheap but I've used things like this to make surface mount an little more veroboard friendly. Surface mount to DIL |
|
|
|
|
Logged
|
|
|
|
|
mpooley
|
|
« Reply #7 on: January 01, 2011, 02:12:51 PM » |
|
I have recently designed (if you can call it that !) and built my own 2408 relay driver board on veroboard.
I used solid state relays fom china the ds2408 chip and a relay driver chip .oh plus about 8 x10k resistors.
Its been working fine for a few months now.
If you want to pm me i can let you have more details.
Oh yes the ds2408 is a complete Heinz to solder, i did use a adapter board at first but i didnt really like it so i made my own (sort of) by soldering 16 fairly stiff wires through the veroboard and bending them so that they matched the ds2408 pins then soldered direct to the pins.
it turned out looking a realy horrible mess but that was mainly due to changing designs. if i was to do it again i think i could make it nice a neat.
Mike
|
|
|
|
|
Logged
|
|
|
|
|
wookey
|
|
« Reply #8 on: January 03, 2011, 04:12:23 AM » |
|
As has been previously discussed, this in indeed something that is obviously useful and yet has not yet become widely available. I believe the correct fix is to get some PCBs laid out and some widgets built. Last time round the discussion got a bit bogged down in safety paranoia about switching mains loads and isolation IIRC. It is true that the best design does depend a bit on what you are trying to switch, but a simple relay design would be a good start. I certainly need some but have got sidetracked from home automation for th last year or so so haven't done anything about it.
|
|
|
|
|
Logged
|
Wookey
|
|
|
|
SimonHa
|
|
« Reply #9 on: January 03, 2011, 10:25:54 AM » |
|
As has been previously discussed, this in indeed something that is obviously useful and yet has not yet become widely available. I believe the correct fix is to get some PCBs laid out and some widgets built. Last time round the discussion got a bit bogged down in safety paranoia about switching mains loads and isolation IIRC. It is true that the best design does depend a bit on what you are trying to switch, but a simple relay design would be a good start. I certainly need some but have got sidetracked from home automation for th last year or so so haven't done anything about it.
I wonder whether we should start by agreeing what the module should do to be useful to the widest audience. Here's a first attempt: - switch 1 or 2 loads (the chip supports 2 and you could half populate the board, or even have an input, instead)
- maximum load 2A @ 240V AC? (like the Hobby Boards ones)
- 1-wire interface (are there other interfaces that could be easily used instead?)
- target price for PCB/components £15?
Nice to have: - a size that's easily mounted in a common plastic box
- relay(s) powered from the network cable to save complexity/components
Notes: 1) I suspect most people will want to switch lights, pumps, fans, boiler thermostats, etc. The only heavy load I can think of is an immersion heater but I think we should rule that out from the start as that would make all the components much heavier for a rare use. 2) I don't know if it's feasible to power the electronics and relays from, say, a 24V DC AUX power pair in the CAT5. We'd need to think about a sensible number of maximum modules on one network. I suppose you could also create a loop to double the current, like a ring main, but only connecting the 1-wire DQ etc at one end of course. Simon PS. Trying to collate previous discussions, here's another one to add to this thread: http://www.navitron.org.uk/forum/index.php/topic,5695.0.html |
|
|
|
|
Logged
|
|
|
|
stevedh
Newbie
 Offline
Posts: 2
|
|
« Reply #10 on: January 14, 2011, 08:01:39 PM » |
|
Sound cool to me.. I want to switch a boiler on and off in my slightly stalled project (always too busy) and have been looking for a suitable 1-wire relay for a few years now  24v aux power is what I would use (I already have the power supply somewhere) as I think that was the highest voltage cat 5 can safely use and we want to keep the amps down. Steve |
|
|
|
|
Logged
|
|
|
|
|
SimonHa
|
|
« Reply #11 on: January 16, 2011, 01:37:30 PM » |
|
- switch 1 or 2 loads (the chip supports 2 and you could half populate the board, or even have an input, instead)
Actually I think an optional input could be quite useful - e.g. (plumbing again!) I've got a remote zone valve that I could control with a 240V switched output and then connect its AUX microswitch from 5V to an input. I think the same 1-wire chip can do both input and output so would just need a few extra components/terminal. |
|
|
|
|
Logged
|
|
|
|
|
wookey
|
|
« Reply #12 on: January 17, 2011, 12:33:27 AM » |
|
Power-over-ethernet is 48V so that must be OK on cat5. I might have 'a friend' who is temporarily using some cat5 to do mains switching (due to cabling expediency) and 'this friend' found that nothing melted in the last 18 months. 'He' really ought to get round to using the wiring as originally intended (drive a 1-wire switching relay, as described in this thread).
|
|
|
|
|
Logged
|
Wookey
|
|
|
|
MikeM
|
|
« Reply #13 on: January 17, 2011, 04:57:55 PM » |
|
I may have a suitable PCB for such a project ? Some time ago I designed a PIC 'universal' relay board. See attached pdf.
8 pin PIC + power supply circuit, signal input conditioning, battery back up, relay on snap off section etc.
I used this for a couple of projects and have about 50 boards 'spare'. I am sure it could be configured to suit this project ?
|
|
|
|
Logged
|
|
|
|
|
ericw
|
|
« Reply #14 on: January 17, 2011, 08:02:49 PM » |
|
The main change to Mikes PCB that would be needed for running with a 1 wire input is that the 1 wire input has to go into INT on pin 5. Fortunately this is quite easy to do by crossing over R3 and R12. (R12 would probably be replaced by a wire link.)
To run with a full speed 1 wire bus you also need a clock frequency of 8 mhz or more. Changing to a PIC12F683 enables this to be achieved with no external xtal and related components. Which would also free up two pins and the jumpers next to the xtal to be used to set the ROMID.
If there is any interest I can do a HalfBee specifically for this board which would look like a DS2405 or a DS2406 so that it can be driven from off the shelf software.
|
|
|
|
|
Logged
|
|
|
|
|
