$8 Lamp (Outlet) "Smart Plug" Module

[sundberg84]

There is a scetch in mysensors lib doing this. Relayaccuatorwithbutton or something. Download the examplescetches and have a look: http://www.mysensors.org/build/relay#relaywithbuttonactuator-example @Mohsin-Hassan

[sundberg84]

@petewill @Moshe-Livne . Coil activates when i try with a 9v battery, so either bad/cheap relays or to weak power plug. All measures +5v but its not enough. Ill order some new relays.

[Moshe Livne]

@sundberg84 IMHO 9v will fry the relay. max voltage is 5.5v if my failing memory serves. depends on your relay, naturally but this is the most common one. have a look at the datasheet https://www.ghielectronics.com/downloads/man/20084141716341001RelayX1.pdf
yes it is 5.5v - nominal 5v, max current is 110%. I am sure it can sustain 6 but 9v will be really pushing it IMHO

[sundberg84]

It was only to test coil failure and see if it was a power issue :)

[Moshe Livne]

@sundberg84 A self fulfilling prophecy :-)

[petewill]

@Mohsin-Hassan said:

Hi,

any possibility of including a push button to manually trigger the switch on and off as well?
And if possible update Vera on the status change.

This way i can make it Wife safe and not get kicked out of the house...

I'm not good with coding but if someone can point me in the right direction please...

We are discussing this over here: http://forum.mysensors.org/topic/1607/safe-in-wall-ac-to-dc-transformers

You want to be careful you use the right transformer so you don't burn your house down. :) The wife probably wouldn't appreciate that.

I really want to do this too. I'm just waiting for the experts to weigh in on which transformer is safe.

[petewill]

@sundberg84 said:

@petewill @Moshe-Livne . Coil activates when i try with a 9v battery, so either bad/cheap relays or to weak power plug. All measures +5v but its not enough. Ill order some new relays.

So strange that it's not working. What is the power rating of your 5V transformer? Do you have a picture of your set up?

[sundberg84]

@petewill @Moshe-Livne

I dont reallt wants to admit it...
Well, I ordered the 5v relay from ebay (i have the reciept!) and looking at petewill video it says SRD-05VDC-
Looking at mine it says SRD-12VDC so probalby the sent me a 12v relay...

New one will arive soon i hope :) Thank you for the help and sorry for clogging the thread.

[Moshe Livne]

@sundberg84 that makes so much sense! And its not even your fault! :-)

[petewill]

@sundberg84 That's good news! Unfortunately you have to wait for new one but at least it's an easy fix!

[hyla]

@petewill
Just out of interest: how did You come up with the length for the antenna?
I remember vaguely that You can calculate the length if You know the
used frequency but You connect Your wire to an already existing PCB-Antenna...

Christoph

[petewill]

@hyla I actually recently did a separate video on how I do this with a little more explanation. If you're interested it's here:

https://youtu.be/NpMnauHeR7Y

In summary, I measured the length of the existing antenna on the PCB then added additional wire to get it up to the required length for the 2.4GHz range (4.92 in).

[hyla]

Thanx :)

Meanwhile I did some research too. The formula (as You all know :) ) is:
Lambda (m) = c(m/s) / f(1/s) with
c= 299711000 m/s
f= 2.400.000.000 hz

which comes down to 0.1248795833333333 m or roughly 4.92 in
The 1.64 in that are used on the PCB are actually Lambda/3.

Nicely done, Pete :)

C.

[sundberg84]

@petewill
Now i got three working relays thanks to you, so again, great video!
Wanted to thank you and also show my sollution.
I hade some 433mhz cheap (not good working) relays with perfect case i could re-use:
The case had a status-led and a switch i use as well.

[petewill]

@sundberg84 Cool! That's nice to have a case like that.

[m26872]

@sundberg84
Nice! That one deserves its own project thread. I think we're many interested in the details.

[Ivan Z]

This is may realisation

[barduino]

Hi @petewill

I've tried this and had inconclusive results rather then a significant extended rage. Not sure what I'm doing wrong or if it's the quality of my RF module.

I've used some wire (8.33 cm) I had left over but its not one solid copper wire, its has many "strings" inside. In your experiment did you use one solid copper wire and can this influence this hack?

Thanks

[petewill]

@barduino I am using solid copper cat5e wire. I don't know much about antennas but it may change the behavior. Do you have any old cat5 that you can cut and test with?

[barduino]

@petewill

I'm going to try it.

I'm also using a capacitor on the RF module, not sure if you did combine both techniques.

On a last note, I've noticed some power setting on the MyConfig.h (1.5 lib) cant remember the values form 1.4.1

/**********************************
*  NRF24L01 Driver Defaults
***********************************/
#define RF24_CE_PIN		   9
#define RF24_CS_PIN		   10
#define RF24_PA_LEVEL 	   RF24_PA_MAX
#define RF24_PA_LEVEL_GW   RF24_PA_LOW

So now I'm initializing the gatweway as

// Instanciate MySersors Gateway
MyTransportNRF24 transport(RF24_CE_PIN, RF24_CS_PIN, RF24_PA_LEVEL);

instead of

// Instanciate MySersors Gateway
MyTransportNRF24 transport(RF24_CE_PIN, RF24_CS_PIN, RF24_PA_LEVEL_GW);

Not sure if there is a significant diference here...

The results i'm getting now (after removing the antena, but with capacitor and changes on 1.5 MyConfig) are similar to the results I got from lib 1.4.1 with capacitor. I have a repeater about 15 meters from gateway and if i put it 17 meters it doesnt work anymore (there are some walls on the way)

I'll just add a solid copper antena to see if results change.

Thanks for the info!

Cheers