Domoticz

gielie wrote: Saturday 12 August 2017 22:04 Your sensor is not working, do you see the led blinking when the water is running, and did connect it to the right pin.

ratjenl wrote: Saturday 12 August 2017 22:35

gielie wrote: Saturday 12 August 2017 22:04 Your sensor is not working, do you see the led blinking when the water is running, and did connect it to the right pin.

Thank you for your quick reply, everything is well connected but the led isn't blinking at all. I will order a new one

gielie wrote: Saturday 12 August 2017 22:44 Try hold it near something iron, see if the led goes on, it should. Check if there is enough power from the pi otherwise try another power source

Hobbybob wrote: Saturday 12 August 2017 22:33

gielie wrote: Saturday 12 August 2017 22:02

Hobbybob wrote: Saturday 12 August 2017 13:55 Hello, I want to include water-usage in my Domoticz as well, and although it will be dificult to get a wire running between the metercabinet in the hallway where the water-meter is and my livingroom where I have my Raspberry Pi, I am guessing it is going to be the only way...

So: 2 questions:
First off: the device in Domoticz you have a screenshot of is a counter that is modified to display water. I can reproduce that, but I also see a type "Counter incremental". What is the difference between these two, and following that: what is the correct one to use?
Aside from that: Can I connect the blue and brown wires to another power supply, and just the black one to the Pi or does that not work? That would save me 2 wires that I have to move through the rooms... Also: is it a problem if the signal-wire is relatively long? Say, 10 meters?

Oh, and do you need to use any resistor or anything before the signal-wire goes ino the GPIO, or can the Pi handle the output from the sensor as-is?

Maybe you can use a second pi for your water meter.

That is also an option. I already ordered the sensor on Ali, so I guess I'll wait for that to come in first, and test with a longer wire before I buy a second Pi (I only have one).

Do you know if there are any resistors or other components involved in this setup?

ratjenl wrote:Well i am trying hard but cannot get it to work. I followed al the steps as described but still this error keeps popping up :

Callback function called!
Traceback (most recent call last):
File "/home/pi/domoticz/scripts/watermeter.py", line 41, in Interrupt
if GPIO.input(21) == 0:
RuntimeError: You must setup() the GPIO channel first

Can someone push me in the good direction ?

Thnx

D'rMorris wrote: Saturday 12 August 2017 23:06
Did you setup your GPIO pin correctly? You have to export it first in sysfs. Is GPIO21 listed in /sys/class/gpio? And if it's listed, is the direction set to in?

gielie wrote:

Hobbybob wrote: Saturday 12 August 2017 22:33 Do you know if there are any resistors or other components involved in this setup?

No resistor needed, just the 3 wires connected to the pi. I ordered this from Ali http://s.aliexpress.com/yUFbiQBZ, makes the connection much easier.

oohlaf wrote: Sunday 13 August 2017 9:02

Really? Aren't the gpio input pins specified as 3.3v max, not 5v.

Verstuurd vanaf mijn XT1562 met Tapatalk

ratjenl wrote: Sunday 13 August 2017 9:32

oohlaf wrote: Sunday 13 August 2017 9:02 Really? Aren't the gpio input pins specified as 3.3v max, not 5v.

Measured with an multimeter it says 5.12 v.

ratjenl wrote: Sunday 13 August 2017 14:54 mine does 5 volt all the time, got it connected on pin40 (GPIO21)

oohlaf wrote: Sunday 13 August 2017 15:09
so by putting 5v on a pin that is meant to receive 3.3v you potentially break your pi.

https://learn.sparkfun.com/tutorials/vo ... ll?print=1

oohlaf wrote: Sunday 13 August 2017 15:09

ratjenl wrote: Sunday 13 August 2017 14:54 mine does 5 volt all the time, got it connected on pin40 (GPIO21)

so by putting 5v on a pin that is meant to receive 3.3v you potentially break your pi.

https://learn.sparkfun.com/tutorials/vo ... ll?print=1

oohlaf wrote: Tuesday 15 August 2017 22:22 Hi,

Yes, you got it right, you can also have a look at this topic:
viewtopic.php?f=17&t=1103&start=40

Hobbybob wrote: Tuesday 15 August 2017 23:34
Great, thank you!

The sensor should be on a boat between China and the Netherlands by now

Milifax wrote: Tuesday 15 August 2017 23:59 Or you could use a cleaner option like a level converter:
https://m.nl.aliexpress.com/s/item/32 ... #autostay

Whatever your choice might be, check the voltage of the signal at the end of your 10m cable. Maybe the voltage drop in the cable gets you to the 3v3. Not plausible, but that way you have your real voltage at the Rpi-end.
And with that measurement, calculate what you need.

Edit: just read a bit more of your thread. Using a separate powersuply for the sensor and only wire the signal is not to be adviced. The GND could have potential difference, or better GND WILL have potential difference. Currents flow and bad readings could occur. Just use the power from the GPIO pins.

Next, why use an extra Pi if all others fail. An Arduino Nano would be a far cheaper and cleaner option. A Rpi for just 1 signal is overkill.
The arduino could be used for some pre calculation if you want as well.