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I2C relay boards.

Started by David Lesher October 25, 2017
I have need for a 8-16 channel I2C in, relay out expansion board. 
We're now using:
<https://www.ereshop.com/shop/free/I2C-RL8xxM_SHEET.pdf> 
but the shipping is insane.

So I'm seeking an alternative supplier. I figure one approach is
to find a forum where Arduino users hang out, and ask there. 

Any suggestions for board suppliers or forums?
-- 
A host is a host from coast to coast.................wb8foz@nrk.com
& no one will talk to a host that's close..........................
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433
David Lesher wrote:
> I have need for a 8-16 channel I2C in, relay out expansion board. > We're now using: > <https://www.ereshop.com/shop/free/I2C-RL8xxM_SHEET.pdf> > but the shipping is insane. > > So I'm seeking an alternative supplier. I figure one approach is > to find a forum where Arduino users hang out, and ask there. > > Any suggestions for board suppliers or forums?
PCF8574-I2C-Bidirectional-I-O-Expander-Relay-Control-SmartHome-Ardiuno-Raspberry https://www.ebay.com/itm/282692860765 US $2.90 Used with: /8-Eight-Channel-5V-Relay-Module-Board-with-Optocoupler-Power-Supply-PIC-ARM https://www.ebay.com/itm/322834065204 US $6.39 gives you eight relays for $9.29 plus some wires between the modules.
Michael A Terrell <mike.terrell@earthlink.net> writes:


>PCF8574-I2C-Bidirectional-I-O-Expander-Relay-Control-SmartHome-Ardiuno-Raspberry
>https://www.ebay.com/itm/282692860765 US $2.90
>Used with:
>/8-Eight-Channel-5V-Relay-Module-Board-with-Optocoupler-Power-Supply-PIC-ARM
>https://www.ebay.com/itm/322834065204 US $6.39
>gives you eight relays for $9.29 plus some wires between the modules.
Seen many versions of that. Want an integrated board w/relays. Found several but all thus far are international $hipping. -- A host is a host from coast to coast.................wb8foz@nrk.com & no one will talk to a host that's close.......................... Unless the host (that isn't close).........................pob 1433 is busy, hung or dead....................................20915-1433
David Lesher wrote:
> Michael A Terrell <mike.terrell@earthlink.net> writes: > > >> PCF8574-I2C-Bidirectional-I-O-Expander-Relay-Control-SmartHome-Ardiuno-Raspberry > >> https://www.ebay.com/itm/282692860765 US $2.90 > >> Used with: > >> /8-Eight-Channel-5V-Relay-Module-Board-with-Optocoupler-Power-Supply-PIC-ARM > >> https://www.ebay.com/itm/322834065204 US $6.39 > >> gives you eight relays for $9.29 plus some wires between the modules. > > Seen many versions of that. Want an integrated board w/relays. Found > several but all thus far are international $hipping.
OK, make your own. A schematic of that board is online.
David Lesher wrote on 10/26/2017 11:35 AM:
> Michael A Terrell <mike.terrell@earthlink.net> writes: > > >> PCF8574-I2C-Bidirectional-I-O-Expander-Relay-Control-SmartHome-Ardiuno-Raspberry > >> https://www.ebay.com/itm/282692860765 US $2.90 > >> Used with: > >> /8-Eight-Channel-5V-Relay-Module-Board-with-Optocoupler-Power-Supply-PIC-ARM > >> https://www.ebay.com/itm/322834065204 US $6.39 > >> gives you eight relays for $9.29 plus some wires between the modules. > > Seen many versions of that. Want an integrated board w/relays. Found several > but all thus far are international $hipping.
I don't follow what is so bad about international shipping? The typical vendor of inexpensive boards is in Asia and ships for free. I found two on eBay that sell 8 channel I2C relay boards with a different form factor for $80 or $90 in the US. Where are you? -- Rick C Viewed the eclipse at Wintercrest Farms, on the centerline of totality since 1998
Michael A Terrell <mike.terrell@earthlink.net> writes:



> OK, make your own. A schematic of that board is online.
Worst option. Avoiding manufacturing anything; just exponential time-sink. Would prefer the integrated board but may end up with split approach. -- A host is a host from coast to coast.................wb8foz@nrk.com & no one will talk to a host that's close.......................... Unless the host (that isn't close).........................pob 1433 is busy, hung or dead....................................20915-1433
David Lesher wrote:
> Michael A Terrell <mike.terrell@earthlink.net> writes: > > > >> OK, make your own. A schematic of that board is online. > > > Worst option. Avoiding manufacturing anything; just exponential time-sink. > Would prefer the integrated board but may end up with split approach.
The split configuration would make it easier to repair, and the control boards can be plugged end to end. You can eliminate the jumpers on the headers with a drop of solder on the underside of the boards. If a relay board or controller board fails, it will be much cheaper to repair. You can buy ready made 40 conductor cables with single Dupont contacts on Ebay to harness them together. I remove the single contact shells and replace them with a single, with the proper number of positions. That way, my projects look a lot neater than the typical wad of individual wires. I may use a pair of these boards in a custom, multiple iron soldering station that I'm building.
Michael A Terrell <mike.terrell@earthlink.net> writes:


> The split configuration would make it easier to repair, and the >control boards can be plugged end to end. You can eliminate the jumpers >on the headers with a drop of solder on the underside of the boards.
> If a relay board or controller board fails, it will be much cheaper >to repair. You can buy ready made 40 conductor cables with single Dupont >contacts on Ebay to harness them together. I remove the single contact >shells and replace them with a single, with the proper number of >positions. That way, my projects look a lot neater than the typical wad >of individual wires.
40? I need some 10 position one-row headers but will likely use two-row 20's and ignore the other. I do plan to plug them end to end but will need to hold them. Thinking a slotted /______\ piece of soft plastic that in turn is mounted to the DIN rail. -- A host is a host from coast to coast.................wb8foz@nrk.com & no one will talk to a host that's close.......................... Unless the host (that isn't close).........................pob 1433 is busy, hung or dead....................................20915-1433
David Lesher wrote:
> Michael A Terrell <mike.terrell@earthlink.net> writes: > > >> The split configuration would make it easier to repair, and the >> control boards can be plugged end to end. You can eliminate the jumpers >> on the headers with a drop of solder on the underside of the boards. > >> If a relay board or controller board fails, it will be much cheaper >> to repair. You can buy ready made 40 conductor cables with single Dupont >> contacts on Ebay to harness them together. I remove the single contact >> shells and replace them with a single, with the proper number of >> positions. That way, my projects look a lot neater than the typical wad >> of individual wires. > > 40? > > I need some 10 position one-row headers but will likely use > two-row 20's and ignore the other. I do plan to plug them end > to end but will need to hold them. Thinking a slotted /______\ > piece of soft plastic that in turn is mounted to the DIN rail.
Yes, ribbon cable. Peel off as many conductors as you need. The color code repeats every ten conductors. T1-3X-40pcs-20cm-Male-To-Male-Female-Dupont-Wire-Jumper-Cable-Arduino-Breadboard https://www.ebay.com/itm/231708399395
Michael A Terrell <mike.terrell@earthlink.net> writes:

>> I need some 10 position one-row headers but will likely use >> two-row 20's and ignore the other. I do plan to plug them end >> to end but will need to hold them. Thinking a slotted /______\ >> piece of soft plastic that in turn is mounted to the DIN rail.
>Yes, ribbon cable. Peel off as many conductors as you need. The color >code repeats every ten conductors.
>T1-3X-40pcs-20cm-Male-To-Male-Female-Dupont-Wire-Jumper-Cable-Arduino-Breadboard
>https://www.ebay.com/itm/231708399395
I'd rather use an IDC connector that matches the headers; less chance something gets loose/ is misconnected. -- A host is a host from coast to coast.................wb8foz@nrk.com & no one will talk to a host that's close.......................... Unless the host (that isn't close).........................pob 1433 is busy, hung or dead....................................20915-1433