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Anonymous Poster #1

Krohne Flowmeter Problem

09/19/2013 1:54 PM

Dear All,

We have one mag. flowmeter (Make: Krohne, Model: Optiflux2000 sensor & IFC300 converter) installed at out site. We are having some problem in this flowmeter. When pump is off that means there is no flow but flowmeter shows some random values. Even when there was not flow in the line for 4 hour...flowmeter was permanently showing some random values. Please advise how can we fix this problem? & what can be reason of this problem?

An early reply would be highly appreciated.

Thanks,

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Guru

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#1

Re: Krohne flowmeter problem

09/19/2013 2:42 PM

Every modern magmeter has a low flow cutoff point, where flows below that value are reported in the display and on the output as zero flow.

The low flow cutoff value might be in percent of span or it might be in engineering units, you'll have to check and see.

So get the manual, find the low flow cutoff setting, check what units it uses and put in a number that will calm those concerned with flutters around zero.

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Guru

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#2

Re: Krohne flowmeter problem

09/19/2013 2:44 PM

1. Read the manual.

2. If you do not understand the manual, get someone who does.

If all else fails call Krohne and ask the tech line for troubleshooting help.

Welcome to the KROHNE Group | KROHNE Group

Here is the Contact information.

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#3

Re: Krohne Flowmeter Problem

09/19/2013 9:01 PM

Have you ever heard of a signal to noise ratio? When one has no signal then one only has noise. Thus a 0 db signal to noise ratio.

I also wonder about the idea that you have no flow when the pump is off. Are you really sure that a siphon or brief pressure wave might actually have some liquid sloshing about occasionally.

You could also just have an intermittent wire.

I think I've reached my WAG quota on this question.

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Power-User

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#4

Re: Krohne Flowmeter Problem

09/19/2013 9:29 PM

You need to Zero the contoller when there is no flow, make sure there is solution in the pipe when you do this.If this fails you then can look at other issues.

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Participant

Join Date: Aug 2013
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#5

Re: Krohne Flowmeter Problem

09/20/2013 2:10 AM

you may want to try hooking a hart communicator since using the button converter is a hassle, make sure that the flow is zero on the line, look for auto zero button, it will automatically set your zero calibration, i had this problem before...if not, you may want to reset to factory settings and try setting again.

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#6

Re: Krohne Flowmeter Problem

09/20/2013 3:21 AM

Make sure there is sufficient dissolved material in the liquid to enable the flowmeter to operate. Below about 50ppm TDS, magflow meters just don't work.

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#7

Re: Krohne Flowmeter Problem

09/20/2013 9:58 AM

Does the pipe remain full when the pump is off? If the liquid level goes below the electrodes, the meter can generate random values.

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#8

Re: Krohne Flowmeter Problem

09/22/2013 7:47 PM

One of the most common installation errors with magnetic flowmeters is improper (or absent) grounding. The EMF induced by a flowing liquid is very small (millivolts or less), and so the slightest electrical power leakage currents traveling through the liquid may be detected as (random) flows.

If you haven't already, check the manufacturer's documentation on proper grounding protocol, and follow those instructions to the letter.

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#9

Re: Krohne Flowmeter Problem

08/12/2024 7:27 AM

In addition to the above, and if the facility exists, consider installing a control that says:

  • If the output from the flowmeter is less than, say, 4.05mA, then call it 4.0mA.
  • If the pump is not running, then irrespective of the output, call it 4.0mA.

and the problem may well go away.

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