In our facility we have level TX (Endress+Hauser FMR245 flanged) on the top of tank of 60C water that part of PH package control. The problem is that the TX gives erratic reading and jumping from time to time (almost every 2 weeks). We have to clean the sensor then it works OK again.

Plz any one can provide help.

waiting replies
thnx

 

I don't know about that specific E&H model, but radar technology in general has a problem with condensed water on the antenna.

If the radar unit is installed where its antenna temperature drops below the dewpoint of the surrounding moist air in the tank then water will condense on the antenna.

Is your every-two-week cleaning task 'removing dirt' or wiping condensed water off the antenna?

Carl

 

Sounds like the transmitter is working okay, but is getting covered in something that you have to clean off every two weeks. Have you considered mounting a spray nozzle where it can be used to wash off the sensor when the readings get erratic? If that's not possible, you might consider seeing if you can use a different antenna, such as a PTFE process seal instead of the interior mounted horn antenna, or the sword or wand antenna.

Otherwise get used to cleaning it every couple of weeks. It is likely that no other radar transmitter will work any better.

You could try a laser transmitter through a glass window if the tank has one.

Walt Boyes
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Do you have agitator in tank ?
RPM ?
CLEARANCE FROM THE WALL?

 

We have a HART FMR 245 that was installed a few months back. We installed 2 transmitters in parallel the other one was a Feild bus FMR 245. The problem is the HART transmitter always fluctuates even if the pump is not running. We entered all the configuration regarding installation and noise adaption, but still we always encounter the same problem. Can you please help me, and why its not happening to the Feildbus transmitter. Thank you very much!

 

Could you please indicate in some form, how the two transmitters are connected. You indicated that they are done in parallel. Why has it been done this way?

Regards,

Tomy Zacharia

 

> We installed 2 transmitters in parallel the other one was a Field bus FMR 245. The problem is the HART transmitter.

That statement is confusing. Mr Zacharia has attempted to get a clarification.

What does parallel mean?

Does it mean that you installed two level transmitters on the same tank?

Or does it mean that two level transmitters somehow share wiring, or a power supply or an analog input or what?