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landis Gyr G350

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By delchrys , 30 November, 2016
Forums
General discussion

Hello,
i want to read my gasmeter L&G G350 with an optical probe(DIY).
But i like to know what is needed for reading out the optical port.
Do i need a modulating IR which modulates at 38khz or is it not needed to modulate the IR signal.
I would like to build my own probe, with the use of a arduino.
Then i need to send "/?!" to the IR transmitter, but how do i do that, do i need to convert to HEX and then send it, or do i need a sort of remote control protocol to send it.

Can someone help me with this, i would like to have more gasreading than once an hour.

Profile picture for user Kurumi

Kurumi

9 years 6 months ago

landis Gyr G350

Hi,

We have clients who have made own optical strobe. There are also some scemas on the internet.
I can't remember address of that web site. You do not change /?! to hex. You just sent it as ASCII.

BR,

Mikko

delchrys

9 years 6 months ago

so i have to create a ir led,

so i have to create a ir led, and phototransistor and then over serial send /?! at 300 baud 7E1.
That should be doable, will try this the next days, hope it works

Profile picture for user Kurumi

Kurumi

9 years 6 months ago

landis Gyr G350

Hi,

Remember that you must use 38khz frequency. I know that there are people who have done this by them self. You can't use example PC's IRDA directly. This might help you.
https://learn.sparkfun.com/tutorials/ir-communication

BR,

Mikko

BR,

Mikko

delchrys

9 years 6 months ago

That's what I meant with

That's what I meant with modulation.
So i does need toto modulate. And then send acai.
Will try to figure it out

Profile picture for user Kurumi

Kurumi

9 years 6 months ago

landis Gyr G350

Hi,

Let me know how happened. For your information: bright sunlight might effect,
so it's good if transmitter is close to meter and not in direct sunlight.

BR,

Mikko

delchrys

9 years 6 months ago

Maybe i build a modulator

Maybe i build a modulator circuit with an 555 timer, or use the timer of an arduino. Have to figure it out somehow. Will update here if it works

delchrys

9 years 6 months ago

Getting no response with

Getting no response with arduino.
Have to figure it out.
Now I have a or led modulating at 38kHz and sending the right command at 300 baud 7e1 in ascii.(I think)
Tried almost every baud rate and parity. Also tried in hex. But no response whatsoever.
I seem not to get it working. Too bad. Have too find some working examples of arduino code

Profile picture for user Kurumi

Kurumi

9 years 6 months ago

landis Gyr G350

Hi,

Remember to send /?!\r\n. 2F 3F 21 0D 0A in hex.

BR,

Mikko

delchrys

9 years 6 months ago

small breakthrough.

small breakthrough.
I have found an optical probe for a fluke multimeter.
I tested it on my electric meter KAIFA MA304 and it responded. YES
I also tested on the G350 but it wasn't responding, maybe it needs different baudrate or parity, anyone who has working configuration specific for the G350???

delchrys

9 years 6 months ago

am i using the right command

am i using the right command for this meter?
/?!\r\n

Profile picture for user Kurumi

Kurumi

9 years 6 months ago

landis Gyr G350

Hi,
Technical documentation from Landis+Gyr G350 gas meter is limited and it's not saying is IEC 62056-21 supported. You can also try with modbus. It's supporting it, but I do not know is it used with optical connection.

BR,

Mikko

delchrys

9 years 6 months ago

Will i get A readout when the

Will i get A readout when the signal is inverted. Maybe i can try a other usb/com cable which supports inverting.
How can I try modbus?

Profile picture for user Kurumi

Kurumi

9 years 6 months ago

readout

Hi,

There are softwares for modbus. Problem is that you need to know register addresses. As far as I know ModBus is not support readout.

BR,

Mikko

delchrys

9 years 6 months ago

Tommorrow i get an other usb

Tommorrow i get an other usb/com cable. Maybe when I invert the signal it works

yctn

7 years 8 months ago

anyone got this to work?

anyone got this to work?

when i just send /?! i get =========================
/?!
as output

when i send: /?!\r\n. 2F 3F 21 0D 0A

i get this as output: /?!
. 2F 3F 21 0D 0A

here is my python script im using:

import time
import serial
import re

ser = serial.Serial(
port='/dev/ttyUSB0',
baudrate=300,
parity=serial.PARITY_EVEN,
stopbits=serial.STOPBITS_ONE,
bytesize=serial.SEVENBITS,
)

while 1:
ser.flushInput()
ser.write('/?!\r\n. 2F 3F 21 0D 0A')
time.sleep(15)
output=ser.read(ser.inWaiting())

print output

print '========================='
ser.flushInput()

Profile picture for user Kurumi

Kurumi

7 years 8 months ago

In reply to anyone got this to work? by yctn

anyone got this to work?

Hi,

Please, if you have a new question make a new topic for it.
You are asking device info using IEC 62056-21 protocol. Your serial port converter is echoing sent data back.

BR,
Mikko

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