Yokogawa Pressure Transmitter

I had to convert this to units I'm familiar with: 0.15 Kg/cm2 is 2.2 psi.

What is the transmitter connected to (what is it trying to read the pressure of)--my first thought would be that the pressure you are trying to read might be above 2.2 psi (0.15 Kg/cm2).

Is it? Do you have an accurate pressure gauge that you can use to check that pressure?

The next thing that needs done is to re-calibrate the pressure transmitter--without knowing what that screw adjustment is on the bottom of the housing, it has almost surely ruined the calibration.

The two things that I can think of are that the line pressure is, in fact, higher than the range that the transmitter is set to or the transmitter is indicating a fail mode. As rhkramer has indicated, checking the line pressure with a pressure gauge would be prudent.

Once you have blindly adjusted a setting without knowing what the results were, all bets are off as to what the real indicated pressure is, though.

Most industrial transmitters have a fail-safe setting, so that if the transmitter detects that it has 'failed' internally, the output goes off scale either up-scale or down-scale.

The up-scale fault levels are typically 21.5mA or 21.8 mA or something in that range.

It might help to Google that model's manual, down load it, read it and see what indicated "error" is telling you.

To properly calibrate, there are 2 adjustments:Zero and Span, and they do interact somewhat on certain transmitters.Apply your low (minimum) signal, and adjust zero.Then apply your maximum signal, and adjust span.Recheck at zero and make adjustment as required.Then check span again.This may take a couple of times for maximum accuracy.

Good luck!

Hi Erlof, I sounds to me like, if the pressure transmitter is working within the set range and still displaying faults it is likely that the transmitter is not set up correctly, is the settings on the transmitter set up correctly, is it set for 0-10VDC or 0-20ma or 4-20ma. But this is not the problem, because you said that the sensor displayed the fault.

The sensor has parameter's that can be set up, is this a new sensor, if so you have to set up the parameter's for your installation. If it is an existing sensor check the parameter settings, if in doubt replace the sensor.

If you could post the sensor spec, this would be helpful to finding a solution to your problem.

Cheers

Joe

Erolf, I agree totally with rhkramer and Iris,

Maybe the differential pressure value that you are measuring with this transmitters is higher that the range.

I have a questions for you Erolf, Where are you measuring this differential pressure? Please tell us if is liquid, air or gas

Are you measuring furnace draft?

Where is ubicated the transmitter above or below the process tap?

How large(long) are the impulse line?

If this transmitter have Hart Protocols use a Field Communicator in order to do a zero adjustment and check with the communicator how much differential pressure is sensing the transmitter, remember that for to do a zero adjustment you must have the same pressure in both sides(high and low) of the transmitter, Normally, this is achieved closing the process valves ubicated in the manifold and opening the bypass valve of the manifold.

In conclusion I think that you must give more information, maybe some drawing or photo showing the transmitter with its installation

Regards

JP

Hi

Please check the following

1. check the maximum working pressure of the instrument written on instrument. If u applied more than that than instrument is damaged.

2. Some time display did not work but output, 4-20 mA, reflects exact output. check with meter the the output.

3. If possible replace and the check for other transmitter.

4. Check internal electronic circuitary and position of DIP switches. Some PCB have calibration of instrument through resistors on PCB, mentioned in catalogue. check that