Is it possible to connect a water pulse flow meter to a 300-S7 Siemens PLC, if yes what is the type of connection ( Profibus , only digital input ) ?

you need an electronic circuit to convert the output of the flow meter to4-20 MA but if the out is4-20 MA you dont need the circuit and connect it direct to an analoge module

u need a high speed counter and program scan cycle should be short

If the frequency of the meter can be handled by the digital input of the PLC you can count by your PLC program and convert to a value to use

Or you can ask the supplier of the meter for a transducer to convert the pluses into common signal4-20mA or0-10V and connect it to the analog input of the PLC

Also you if teh meter supports profibus connection it can communicate with the PLC, but the PLC should be the profibus master.

dear sir

1st you must determine the type of your flowmeter and the rate of the i/p and o/p and the wave form of the o/p

connection type profibus

Yes, it's possible with extra Pulse/Analog converter "SIL"

Input for SIL device high-frequency pulses from Flow meter

Output4- mA or (0- mA,0- V) other signals to the AI module.

The range of4- mA should be proportional to the min/max range of flowmeter.

One more thing, some of the flowmeters are equipped with analog output, and such cases pulse converter device not required. You can connect directly to the AI or if Flow Meter support Profibus, you can use as well!

Thank you!

Sir, I did not work with Siemens PLC, but I have made some googling and find this pdf file for your interest.

https://www.automation.siemens.com/doconweb/pdf/SINUMERIK_SINAMICS_03_2013_E/S7300Re2.pdf?p=1

you will also find this Control Engineering blog site very much helping.

http://www.control.com/thread/

Thanx.

you need to convert the pulse signal into 4-20mA loop current or 1-5 volt signal,

Yes we can use it with the analog input for PLC , we have to us Profibus .

Yes it possible.You will use a flow meter that can  generate an output of 4-20mAP  and connect the output to analogue module of the PLC using a PROFIBUS.