Emerson Exchange 365

In reply to Rein:

Hello Rein,
I completely agree with you that, even though the unit is erratically set up, you should at least get an erratic reading out of it. A missing antenna will definitely be a cause for erratic readings and/or missing signals. The unit may work for a while, but as the time passes, build-up may form inside the nozzle and change the geometry for the microwaves and thus cause an totally erratic behaviour. You will hopefully find that that is the case here. Still, we cannot totally rule out that the unit itself is broken, so plots (a.k.a. tank spectras, echo curves) from the unit will help us forward with the matter if the new antenna doesn't help. Please keep us updated about the progress and we will do our best to assist you!
Kind regards,
Ingemar

In reply to Ingemar Serneby:

Hello Ingemar,

I'm back again after a long wait. Here are the updates on the radar transmitter.

I installed the 2" cone antenna and still, it did not clear the problem.

I hooked up the 475 and here's what I found:

1. The Microwave Module Status shows Invalid Reference Pulse. What does this mean?

2. I tried to Search for Surface and run the Measure and Learn but it failed due to built-in status response.

3. When I simulate, all Primary Values Status become Good_NonCascade, including the signal strength and the LCD displayed the simulated value. I did not activate the volume as I don't need it.

But when I stop simulating, all Primary Values Status goes BAD::Non_Specified and the LCD displayed "-- -- -- --" again.

4. Also, the Transducer Type is showing "-----------------". Is this normal?

5. And lastly, I removed the 2" cone antenna and repeated what I did from 1-4, and the result was the same. No change.

What could be the reason why it is not working properly?

Thanks again.

Rein

In reply to Rein:

Looks like the problem is that the signal between the transmitter head and the antenna is missing (ie. the reference pulse). The transmitter came from Emerson Middle East.

In reply to Rein:

Hello Rein!
I am sorry to hear that the antenna didn't resolve the matter. As mentioned in my previous replies, it might very well be the transmitter head itself that is causing the main problem. The "invalid reference pulse" is likely caused by an electrical failure within the microwave chain as it is supposed to generate pulses used both for reference and for measurement. Did you have an opportunity to look at the tank graph / plot view? Or even make a photo of it for our review? If it shows a flat line rather than pulses, the answer then is very clear; the transmitter head most likely need to be replaced.
Best regards,
Ingemar

In reply to Ingemar Serneby:

The transmitter is unable to "Search the Surface", create an "Echo curve", or even do the "Measure and Learn". I can't generate the tank graph.

In reply to Rein:

Hello Rein!
It is very likely that the transmitter is broken and I thus recommend you to have it replaced. Even though a missing antenna may result in similar behaviour, I think that you have proven that the problem remain with an antenna in place - and I find it unlikely that erratic configuration is the root cause as this unit has been in operation previously. Also the missing reference pulse alarm is a strong indication that something is wrong with this unit.
Best regards,
Ingemar

In reply to Ingemar Serneby:

Hello Ingemar,

I was able to get the Echo Curve. Below is the screenshot.

Could this be a sign that the transmitter is actually faulty?

Because, I can't see any failure activated in the diagnostics under Resource Block.

And the device status shows GOOD.

In reply to Ingemar Serneby:

Another strange thing on this Rosemount product is that, it did not even show in the parameters the Microwave Module or Hardware Error.

Only the Invalid Reference Pulse.

I'm sure the microwave module is damaged.

Thanks a lot Ingemar for your time in answering my queries. I can consider it solved. We will just replace the hardware.