M-Bus to C-Bus interface

Hi All,

I have been looking at my options to bring energy meter information from a M-Bus network onto C-Bus (no BMS as such just C-bus onsite) to display in a Citec front end.

The electrical engineer has put forward the TAC Xenta 913 a a solution to convert M-Bus to C-Bus but after reading how to configure this device, it appears to me that you need a PC running the software - TAC Vista, to handle the translation from one language to another.

Am I correct in this or am I mis-interpreting the information.

The engineer does not want to run more communication networks than necessary and would like to bring everything onto the C-bus network and have one pink cable run back to the controlling PC. I would prefer to have as few PC's and different pieces of software running as possible and to this end would look at running an M-Bus and C-Bus cable back to the Citec front end.

As I have not had much to do with M-Bus could anyone let me know the maximum comms cable length, and inherently how far can a signal from an M-Bus power meter travel, do you need a signal booster etc??

Any hints or suggestions on best practise to do this would be much appreciated.

 

Yes, your right - can set up configuration from PC and then have gateway as stand alone. One stumbling block is that the TAC Xenta only has one RS232/485 port and both C-Bus and Meter-Bus will communicating on RS232. Could use 2 x TAC Xenta 913's but this would be expensive.

If anyone has used another gateway that can translate Meter-bus into C-Bus please let me know.

If no real gateway answer is out there, I will recommend C-Bus and Meter-Bus comm's cables be brought back to Citec PC. Citec can then talk to both.

 

I'll start by saying that I know nothing about M-Bus or what it is used for (never heard of it before).

Why do you need to get M-Bus onto C-bus if Citect can do the job itself.

While you state that you don't want more comms networks than necessary, you are adding more hardware and most likely losing some functionality at the same time.

What about introducing OPC - C-Bus has an OPC server lurking somewhere and M-Bus may have one.

The other consideration is that adding the M-Bus traffic onto the C-Bus network may increase the traffic to a point where it is sluggish.

From an industrial automation/Mechanical/Electrical engineering point of view, I would be more inclined to convert both to Ethernet and let Citect connect via Ethernet, but I have no Citect with C-Bus experience.

Mick

 

Ian,

M-Bus has been around for some time. It uses a very basic signalling method of voltage / current shifts on a two wire bus to indicate binary space and marks. It uses a master - slave arrangmenet where the meters are the slaves.

I can't imagine why you would want to convert M-Bus packets to C-Bus Messages ???

The TAC Xenta 913 is a pretty powerful gateway with a price tag to match. You will also have to pay for commissioning and provide a C-Bus PCI which will all add up $$$

Why wouldn't you take the straight forward path and send the M-Bus direct to Citect ????

There are many M-Bus converter products that can get you quickly on to 232/485/Ethernet... Yell out if you need help with a converter.

 

Hi All,

I agree with both your previous comments.

We had been asked the question by the Electrical Engineer in charge of the job and so I was just making sure I had all the right answers for him.

My recommendation has been to bring Meter-Bus and C-Bus back to the Citect PC and thus cut down on gateways, and as you rightly said reduce unnecessary traffic on the C-bus network.

How we bring this data back to Citect either over Ethernet or a seperate C-Bus and Meter-bus network will have to be decided upon.

FYI a PiiGAB Citect M-Bus Driver for 20 power meters is 500 Euro's.

Thanks for all your replies.

 

Hi All,

I agree with both your previous comments.

We had been asked the question by the Electrical Engineer in charge of the job and so I was just making sure I had all the right answers for him.

My recommendation has been to bring Meter-Bus and C-Bus back to the Citect PC and thus cut down on gateways, and as you rightly said reduce unnecessary traffic on the C-bus network.

How we bring this data back to Citect either over Ethernet or a seperate C-Bus and Meter-bus network will have to be decided upon.

FYI a PiiGAB Citect M-Bus Driver for 20 power meters is 500 Euro's.

Thanks for all your replies.