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Posted By: ricker avery weightronicsSilo level indicators - 02/11/08 05:42 PM
Hello, the aggregate plant I work at uses a great deal of siemens-milltronics control equipment for silo level indicators. They also use this brand for their belt scales. I recently replaced one of these belt scales with a Beltweigh system, which has worked flawlessly since its installation, whereas the siemens lasted about 3 days. Unfortunately, Beltweigh doesn't deal in level indicators, so I would like to know if anyone can recommend another brand of level indicator to replace the siemens. In addition to their products being unreliable, they offer very poor customer service. Thanks.
We use pressure, level, temp, and pressure diff instruments from Rosemount


Trouble Free for the most part
Posted By: Redsy Re: avery weightronicsSilo level indicators - 02/12/08 02:13 AM
I used Rosemount for 20+ years with very few, if any problems at all.
Are you talking about solids? I also used Weightronix and Fairbanks load cell systems for weight-based measurements.
My main problem with Milltronics has been that the Tefzel surface of the ST-H transducers delaminate from the filler. Energy gets eaten up in reflections on both Tx & Rx. The units I deal with have a parameter 83 which displays dB/uV. A delaminated surface will usually cause a level >60dB, to drop to the teens or 20s. You can press against the hard surface and feel a little give when this happens. I couldn't tell you the number of these that we have replaced at around $500/unit. Finally, I started scoring the surface along the outer edge and peeling off the Tefzel. The filler within has a little give to it but exhibits good dielectric resistance the piezo within is still protected.

You really need the programmer to deal with these units. The signal thresholds for short and long pulses can be changed as the transducer reaches end of life.

The only other problem I have had is a failure of a very small Belling-Lee (English) fuse on the main board. I could only find one US supplier in Florida and they had prohibitive minimum order quantities.

Joe
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