i have to get the totalizator value of a flow meter to be displayed in other units with MODBUS protocol. the flow meter generates a pulse for totalizator value. how can we communicate?

 

Hello,

You can add simply microcontroller like PIC with modbus slave protocol (see www.modbus.pl) and connect the pulse output to the PIC to count the flow.

Regards
Andrzej

 

I think you are saying you need to convert pulses from the flow meter to an accumulator that resides in a Modbus Slave. It can be done with almost any RTU supporting a Pulse Count Input(s) AND ModBus but that is not inexpensive.

Now being really cheap, using an old PC with two Serial Ports, have one Serial Port count the pulses through RxD and the second Serial port talk Modbus. I can give you the program that can handle that type of interface if you want.

 

What is the brand and model of the flow meter? And what is the flow meter monitoring (water, gas, etc)?

Depending upon the flowmeter that you have, there are several really good options that I know of and have used in the past...

 

I have the similar case. I had some flow computers that I want some of their data and monitoring them in a PC. The flow computer is Mobrey 7955. Could I use the solution you have recommended for totalizer?
May I have your email address to receive the solution you have stated in your reply?

Regards,
Vahid

 

Our flow computer is Mobrey 7955, and the fluid is Crude oil, the floe element is orifice. I want to get the data(Measure value) from flow computer and monitoring them in a PC.

Regards,
Vahid

 

Vahid,
The 7955, depending upon which communication options it has, may support MODBUS/RTU or MODBUS/ASCII on its serial port... or MODBUS/TCP on its Ethernet port.

Here is the brochure for that flow computer...

http://www.documentation.emersonprocess.com/groups/public/documents/brochures/d351484x412.pdf

Interrogating flow and totalization directly from the flow computer's internal Modbus registers (via serial or Ethernet) would be much more desirable than a pulse-counting solution.

I'd recommend finding out whether your particular model features Modbus support. If it does not feature Modbus, then I'd recommend checking whether an upgrade kit is available.

 

zabee,

If you wish to interrogate totalization and flow rate from water meters, then my company offers a direct-read Modbus solution for many water meters that eliminates the need to count pulses.

Our device is the EtherMeter, and it reads encoded water meters directly using the AMR (Automatic Meter Reading) protocol, without the need to count pulses (and without the inevitable totalization errors that result from pulse-counting).

The EtherMeter provides the totalization and flow information to a connected control/SCADA system in Modbus format (RTU/ASCII/TCP). DF1 and EtherNet/IP protocols are also available for Allen-Bradley control/SCADA systems.

The EtherMeter can read water meters from the following meter manufacturers: Sensus (Rockwell), Neptune (Schlumberger), Badger, Actaris (Itron), Elster-AMCO (ABB/Kent), Metron-Farnier, Hersey, Master-Meter, Sitrans (Siemens), and perhaps others.

Further information is also available at our website: scadametrics.com

Hope this helps.

 

Scadametrics:

Our flow computers (7955) do have the serial port which supports the Modbud RTU, RS232,RS485. I am looking for a solution to use this feature, is there a specific software to install on a computer and gathering the data from some flow computers with above mentioned model number?

I would be thankful if you could advise me on this issue.

regards,
Vahid

 

I believe that you will need two pieces of software... one for data collection/communication via Modbus (an OPC Server) and another for graphical data presentation --- HMI (human machine interface) software.

An example of an OPC Server is KepServerEX (by Kepware), and an example of HMI software is Wonderware.

However, there are MANY OPC servers to choose from, as well as many HMI programs to choose from, as well.

I'm not the best person to provide advice as to which is best... the best solution also probably depends upon the specifics of your application. Hopefully, some others here will add their opinions.

 

You need to go to the Emerson Mobrey website and download one of the Windows based programs such as FC Config.

There is also PC Connect which is probably more use when configuring your flow computer byt FC Config lets you set up list functions where you build a list of all the data you want to download and then you use FC Config to data log - you set up what parameters you want to log but in this case ou just log the list.

You can log whatever you want and use DDE export to put it straight into excel and thus in excel you can set up live graphing solutions of each of the parameters. The data logging function saves the data as exel spreadsheets or as delimited text files.

Correction. MicroMotion now only show as Prolink to download and the documentation suggests it will work with 795x but I have grave doubts about this and about using it. I have found Prolink to be a considerable nuisance when trying to set it up to monitor coriolis meters. Better you contact Mobrey service and request a copy of FC Config with the *man and *mnu files for your software version.

 

Thank you for your reply.

I have the Fc config,the FC config can only read the data from one flow computer at a moment. if the flow computer is connected to more than one flow computer, then I do think thatwe could use your solution? Am I correct?

Also could you guide me how to insert the data into Excel/ or using DDE for this issue.

Thank you for your time.

Vahid

 

Hi,
I am looking for a water meter and a gas meter that can output Modbus, LonTalk, or BACnet. Do you know of any product?

Thanks,
Steve

 

For your application, I recommend using a Sensus water meter and a Sensus gas meter, both of which communicate their readings using an industry-standard meter protocol.

And my company manufactures a device -- the 'EtherMeter' (see ethermeter.com) -- which can translate one or two meter readings that use this standard meter protocol into the Modbus protocol (Modbus RTU/ASCII/TCP/UDP). FYI, it also translates into Rockwell/Allen Bradley protocols, as well.

In this case, one of our translators would be able to handle both the water meter and the gas meter.

Here's a link to Sensus' water meter register:

http://na.sensus.com/Module/Catalog/File/water?id=145

Here's a link to Sensus' gas meter register:

http://na.sensus.com/Module/Catalog/File/gas?id=254