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Controlling a Flow Transmitter using PLC
Determining flow quantity going to my tank using a flow transmitter and PLC, Allen Bradley and RSLogix 500

Hi, please I wish to develop project like this:

I wish to control my flow transmitter using PLC. For example If i wish to pump 1000, 2750, or 3800 gallons of water into my tank, the command should be given from RSLogix 500 software in my PC. After pumping the 1000 gallons, the valve should switch off. They should be a possibility were the task can be done anytime inputting different amount of gallons.

I wish to use Allen Bradley 1400 PLC to perform this task. My flow transmitter does not support Ethernet option! What types of instructions are used in RSLogix 500 to build this type of application?

You seem to be describing a need for level control and automatic cut-off.

What is the overall process description?

1 out of 1 members thought this post was helpful...

A flow transmitter measures and reports the flow rate. A PLC does not control a flow transmitter because the flow transmitter just a flow rate reporter.

A valve (in the pipe line) controls the flow. An actuator moves the valve stem to position the valve in order to adjust to a different flow rate. A valve positioner accepts a command signal from a PLC and communicates to the valve actuator which positions the valve to produce a different flow rate, which the flow transmitter measures and reports.

What you describe is called a batch operation. There are stand-alone, commercial batch controllers where one inputs the desired amount (preset). The batch controller reads the signal from the flow transmitter and controls the valves, shutting off at the appropriate time.

Or you can do batch control with a PLC, but then you are the systems integrator putting all the pieces together to make them work.

Hi thanks for the reply

>You seem to be describing a need for level control and
>automatic cut-off.
>
>What is the overall process description?

please you can email me at nyameephraim@yahoo.com

I wish to design an automatic flow control for batch.

scope of work is, for example, an operator needs 1000 gallons of water in the batch, he should give command to the appropriate register in the PLC. they should be a kind of accumulative scaling counting on this. once is 1000 gallons, it switches off the pump automatically. and the accumulator should rest automatically too.

for this project i wish to use pulse application of Endress + Hauser flow transmitter to communicate to the analogue input card of my PLC.

I have an Allen Bradley 1400 PLC

Please i will be happy if you can help me elaborate the RSLogix 500 instruction that works for this application best.

Best Regards
Ephraim

By Steve Myres on 8 February, 2019 - 1:16 pm

A pulse flowmeter output will probably not be compatible with an analog input on the PLC. Sometimes there are PWM signals that an AI will time average into an analog equivalent, but flowmeter pulses generally refer to a specific volume per pulse and are not PWM. While you can get flow rate from frequency of that type signal, if you're primarily interested in flow rate vs. totalizing, then your signal would probably traditional analog like 4-20ma or 0-10V.

Hi,

>You seem to be describing a need for level control and
>automatic cut-off.
>
>What is the overall process description?

Please i wish to do batch totalizing (automatic flow control). i wish to use Endress+Hauser flow transmitter with Allen Bradley 1400 to do this control. for example, if i need 1000 gallon in my batch, i should give an instruction to the PLC once is 1000 the flow should switch off. i wish to do this using the pulse output of the flow transmitter.

please i will appreciate if someone can help me with sample project for this to elaborate me more.

thanks
my email. nyameephraim@yahoo.com

To connect your flow transmitter to the 1400, you should add the I/O required to do the job (analog, pulse, etc.) if the PLC doesn't already have it. We have successfully implemented a very similar application, totalizing flow transmitter's pulses, using a 1400 PLC. The 1400 Ethernet port is not designed for polling anything, it is best for IHM hook-up and programming purposes. The flow transmitter we used is an Endress + Hauser, with the proper output options.

thanks for the reply

>To connect your flow transmitter to the 1400, you should
>add the I/O required to do the job (analog, pulse, etc.) if
>the PLC doesn't already have it. We have successfully
>implemented a very similar application, totalizing flow
>transmitter's pulses, using a 1400 PLC. The 1400 Ethernet
>port is not designed for polling anything, it is best for
>IHM hook-up and programming purposes. The flow transmitter
>we used is an Endress + Hauser, with the proper output
>options.

Hello please here is my email: nyameephraim@yahoo.com
kindly email me please i will need some elaboration from you. this forum i did thing we got any notifications we reply comes in
i wish to explain the project to you in details.

thanks