Hello,
I’m trying to connect a CO sensor to HMI through Modbus protocol but I couldn’t.
Any solutions?
Thank you
I’m trying to connect a CO sensor to HMI through Modbus protocol but I couldn’t.
Any solutions?
Thank you
????Hello,
My watch stopped working and I tried to fix it but I couldn't.
Any solutions?
Thank you.
Unfortunately I’ve reported you due to your rude attitude and trying to mock the members. Hope you find a group in your brain level.Hello,
My watch stopped working and I tried to fix it but I couldn't.
Any solutions?
Thank you.
I'm good with that. And, I've already reduced myself to your level. I'm going back up where the air is a little fresher; it stinks down here.Unfortunately I’ve reported you due to your rude attitude and trying to mock the members. Hope you find a group in your brain level.
Transmitter:It's unusual to attempt direct connection of field device to HMI.
Can you provide a few more details of the HMI and CO sensor, connection details
and the results of your attempts at connection.
I don’t know you.Have a look at my (MANY) posts. I ask a LOT of questions, sometimes for the same requests which have been answered many times. I try very hard to be patient; sometimes I don't succeed. I get a few comments from other posters/responders that I have the patience of Job (though it's a nice compliment, it's not true). I just try to remember what it's like when one is new to the industry and engineering. But, your post is so typical of people these days. One sentence "description" of the problem. You used a question mark; many don't, but did you ask politely. "Can anyone offer any solutions, please?" (Of course I know there are some cultures and locations in the world where this is not a word for please.... so I generally try to look past that.)
I ask you, Mpanahipour, how would you answer your own original post? What information would you need to be able to respond? Come on, how would you respond to your own post? What solution would you recommend first? Tell us, please. (See, I can be nice!)
So, what solutions would you recommend in your first post, sir? Inquiring minds want to know.
I also have mentioned to the vendors.Mpanahipour,
Welcome to the forum! There are many knowledgable and helpful members here that can help you, however, we need you to be more precise and detailed with your questions. Please understand that the members here take valuable time away from their normal work schedules and lives to help others. By providing as much detailed information as possible, this reduces the valuable time we need to spend understanding your particular issue and can help you solve your issue more quickly.
So to start, please provide us with the following information.
- What is the vendor and model of the CO sensor?
- What is the vendor and model of the HMI?
- What version of Modbus are you using? Are you using Modbus RTU over an RS-485 connection? Are you using Modbus/TCP over an Ethernet connection?
- How do you have the CO sensor connected to the HMI? Please detail all RS-485 wires or Ethernet cables, Ethernet switches etc.
- What are the Modbus configuration settings you've tried on both the CO sensor and HMI to establish Modbus communications? Please provide details on settings such as baud rate, parity, address, IP address, port number, etc.
Thank you for the additional details.I also have mentioned to the vendors.
The connection is Modbus RTU over RS-485 port.
baud rate: 9600
Parity : none
Thanks for quick reply.Thank you for the additional details.
How do you have the CO sensor connected to the HMI? Please detail all RS-485 wiring connections
Have you confirmed that the baud rate, parity, and address (slave address in the CO sensor, target address on the HMI) settings match in both the CO sensor and HMI? Please note that sometimes you need to power cycle devices for settings to take effect.
Although it's called 2-wire RS-485, it actually requires 3 connections - RS-485 +, RS-485 -, and signal reference (i.e. common, ground, etc.). Additionally, the A and B terminal labeling is not standardized in the industry, so you may need to swap your + and - wires.I’m using 2 wires configuration
Cermate PK HMI | Honeywell E3Point | QEL Q5 |
RS485+ (Pin 1) | A or B | RS485-A or RS485-B |
RS485- (Pin 6) | B or A | RS485-B or RS485-A |
SG (Pin 5) | GND/Shld | GND or 24VAC neutral |