Hello,

I have an S7-300 PLC with DI/DO AI/AO, I want to real values from a E+H Promag 33 flow meter, how can I achieve this? 

Regards,

Hello ldi`;

Depending on the model of Promag 33 you have in hand, it may have a 0/4-20 mA output that you could connect to one of your PLC analog input channels; the pinout will vary depending on the model, see pages 9-10 of the following document. All models seem to have a pulse output, that you can connect to a digital input to count the pulses.

http://www.shlevel.co.kr/ehprduct/pdf/PROMAG33.pdf

If you are not sure, you should contact your nearest E+H rep to locate the necessary documents and identify the exact model of transmitter. (the Promag 33 manuals are no longer available on the Endress Hauser webisite

You probably will need to use the keypad on the flownmeter to configure the analog output; ask them about the operations manual at the same time.

Hope this helps,

Daniel Chartier

Hi,

According to the manual, I can even use it for Profibus DP, right? If so, how do I configure it on TIA? Also, for the pulse DI, what function on TIA will allow me reading this?

Regards,

Hello ldir;

As stated, the type of output possibilities for your Promag 33 transmitter will depend on the model you have. If your model is Profibus-DP, then you can use the adequate gsd file and integrate it as a slave to your network.

So begin by finding out what model you have, starting with the information on the nameplate. If you have no idea what model you have, contact E+H reps and ask them, based on the model number.Then choose what output channel you will use.  Also request the gsd file if you can use Profibus.

Look for the operations manual of the Promag 33 (or ask E+H) as it does not seem to be available on their site. Youy will need it to commission the transmitter for the outpiut channel you select.

For example, if you decide to use the pulse oputput, you will have to connect it to a digital input of your PLC. Then use a counter to count the pulses that come in. In the commissioning manual you will find out how to program the transmitter to send a pulse for every... 10 liters, 100 liters, 1000 liters... or whatever you select. Now if you pulses come slow enough you do not need anything special for the DI. If they come too rapidly for a standard DI channel, you will need to implement a High-Speed Counter (HSC).

If you select receive a 0-20 mA or 4-20 mA signal; in the PLC you will have to scale this value to read the engineering value you are using in your project.

Hope this helps,

Daniel Chartier

Hi, 

I got the manual, I have three type of outputs only,  4-20 ma,  Pulse/frequency and relay output. Now for my case I have for digital and analog modules. Which one is best to use? 

Regards,

Hello, I am going to choose AI 4-20 mA. I have,  Analog input module SM 331; AI 2 x 12 Bit; (6ES7331-7KB02-0AB0). Do you mean that I will connect Pin 26 to M0+ and Pin 27 to M0- with D as the  Measuring range module setting? 

Regards,

Hello ldir;

When you connect a current-transmiiting sensot to an analog module, you must take into account how the power is provided to the sensor.

- power can come from the analog input channel, looping thorugh the sensor and connected back at the analog input. In Siemens terms, this is a 2DMU connection (2-wire sensor, passive).

- power can come from the sensor's integrated power supply, and the 4-20 mA signal is generated by the sensor and connected to the analog input as an active node (4DMU connection, 4-wire sensor, active).

To distinguish between the 2, the measuring range should be placed on "C" for 4-wire sensors (your case) and "D" for 2-wire sensors.

See the attached screenshot from the same manual you showed earlier (S7-300 Module Data).

Next you will have to read the correct PIWxxx input and scale the analog value. Will you need help to do that, or are you able to find most of your answers by yourself?

Hope this helps,

Daniel Chartier

Hello,

How did you know that I need a 4DMU and not 2DMU? I can't still figure out how you manage. When I read voltage across Pin 26 & Pin 27 I get 24vdc. Now, how do I connect them to my AI? I only know how to connect it when it comes to voltage measurment. For scaling, I just use use the scale function as in voltage right? 

regards,

Hello ldir;

Look at the screenshot you provided earlier, showing the connections on your AI module.

Notice the "2DMU" and "4DMU" columns? Examine the 2 connection schematics, feel the difference between the two designs. 2DMU connects the analog input (which will generate the 24 VDC required for the transmitter) to the sensor and loops back to the analog input channel; 4DMU shows independant power connections on the sensor, which is why it is called 4-wireL: 2 wires to the power supply, 2 wires to the analog input.

Now, disconnect the power inputs on your flowmeter. How much voltage do you read on your pins 26 and 27  now? None, right? That means the current transmitter on the flowmeter works when it receives its own power and can produce the basic 24 V required for current transmission, and acts as an active partner on the analog input of the PLC.

So follow the 4DMU connections shown on your own diagram. + on pin 2 and - on pin 3.if you choose to connect to CH 0. Do not forget to open the analog module's configuration in HWConfig and make sure all parameters are correctly setup for 4DMU connection.

Hope this helps,

Daniel Chartier

Hi, 

I could not read from the AI, Configuration on TIA is OK. You can see my wiring on the post below. I'm now getting 7FFF using a move function and yet the signal is constantly chaning. Note that I am getting 24 VDC across Pin 26 and Pin 27.

Best regadrs,