Climaveneta - Modbus communication

Hello,

My name is Davide, I work in the Republic of Ireland as Site Engineer for a pharma company.

I'm trying to setup MODBUS communication between our ABB DCS system and a Climaveneta FOCS unit equipped with the 485 MODBUS comm card on their W3000 controller without success: is there any body that did manage to link up with a Climaveneta unit through 485?

I'm not looking for somebody to sort the problem for me, i would just like to know if there is anybody that actual setup such communication or if it is just theory written on the manual.

Thanks

Davide

Hi Davide,

Just a few thoughts......

What length cable? Correct cable impedance?
Correct termination?
1 to 1 or are there other RTUs on system?
2 wire or 4 wire ?
Only Earth Screen at one end and daisy chain units.
Only 1 Master.

ECM

What are your problems? Hardware of software? Do you get any ascii transmitted or nothing at all?

Hi,

Thanks for answering so quickly.

So far i'm pretty sure that all the main setting/parameters are ok:
- termination looks correct (Txd/Rxd/Shield)
- 120 Ohm resistor
- cable length 80 meters, AWG 22 twisted and shielded
- 2 wire
- at the moment the chain just consists in 1 master and 1 slave (chiller), if it works i will then look into adding other 8 salves (energy meters)
- address and baud rate set consistently
- as far as i can understand there is no communication at all, the master times out after polling the slave. If we connect a different device that supports 485 in place of the chiller we are instead able to see it on the DCS

...it might be the comm card on the chiller controller being faulty, i'm just trying to find out here if i'm missing something big and obvious for somebody expert in the field before ordering a spare that might not even solve the problem

...by the way, i must really congratulate with who is responsible of this forum and to the people that write on it: i found it through Google, i had a look around in the last hour and i must say it is a very valuable source of information, especially for those like me who are not refrigeration engineers.

Davide

Hi Davide,

Do you have to 'enable' comms on the climaventa unit at all?
Are you using a valid data address? Off the top of my head, 3000 up are Modbus read locations

Hi!
I already did it some times on W3000. Problems was not. What exactly does not work?
For search of variables use chipkin.com/cas-modbus-scanner
Further OPC-server and Scada
In parametres check up it is included "USER"\Serial line configuration- enabl.

Hi

Yes, on the W3000 (onboard PLC, i just discovered it is a PLC from CAREL) you actually have to enable the serial communication specifying from "supervisor" - which we did from the start - then you enter the ID address and the baud rate.

The more i read you're replies the more i think it is just the card (or part of the PLC code related to the serial comm) not working properly, so probably the best solution is trying with a new comm card and see if it works.

Thanks for your suggestions and for the link to the chipkin modbus scanner, if i manage to get a result i'll post the solution here...even if it will probably take few weeks

Thanks again

hi davide,
you are site engineer , right, is it your job to wire in this controle sytstem , are you qualified and experianced to do this job? have YOU done this before?

Hi sedgy,

It is not my job to wire and set-up the communication.
Unfortunately, here we are a very small staff: it is enough to do what is strictly needed but if you want to go a bit further you get to do a bit of everything.

In this case I am just trying to understand where the problem is and what can be done to solve it beacuse the Automation contractor says the problem is on the chiller while the refrigeration contractor says it is on the DCS... it is not a vital issue as we run the chiller on time bands with two different set-points, so the process is not affected at all by this comm problem.

I want to have total control of the chiller from the DCS so that we can achieve a more precise regulation of the set-point in relation to the particular production step: this would then result in saving a significant amount of power every week by increasing the T set-point whenever possible. Time bands are great but are not too flexible.

Davide

Quote:

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Originally Posted by sedgy

hi davide,
you are site engineer , right, is it your job to wire in this controle sytstem , are you qualified and experianced to do this job? have YOU done this before?

---

If you are not ready to help people, just browse away, and please don't annoy us with stupid answers. :(

Had same probs communicating to 3000 controller. Set address and baud rate the same on controller and laptop program but still not communicating. Tried using carell default settings and is now ok. Even if controller settings differ set these figures onto laptop program and should work. These are address 77000 and baud rate 38600. If requested carel default password 1234. Strange that it works with addresses and rates being different from controller to laptop program but it did.
CHEERS

Thanks AusMech but it really looks the problem here is on the comm card on the carel controller.
I'm waiting for a service engineer to come onsite towards the end of November with a new card... hope that will work

Davide

There should be LED lights flashing (green) on field card on controller. If not flashing card not inerted correctly ( they can be tricky) or faulty serial card.