Sigma 980 - User Manual

Questions and Answers

K
Katie MiddletonAug 2, 2025
What to do if Sigma Measuring Instruments flow meter loses echo?
- K
  Keith RichardsonAug 3, 2025
  If your Sigma Measuring Instruments flow meter is not getting a return signal from the sensor, it could be due to several reasons. First, check for excessive foam on the water surface, as foam may cause sound waves to be absorbed. Inspect the sensor cable for any cuts or nicks and ensure the connection between the flow meter and the sensor is secure. Verify that the sensor is level for proper signal return and try shielding the transducer from convection currents. You might also repeat the temperature calibration procedure, as extreme high or low temperatures may indicate a faulty temperature sensor. As a last resort, try a different sensor on the same flow meter to rule out instrument problems and try a different flow meter with the same sensor to rule out sensor problems.
R
rachelbrownAug 10, 2025
How to troubleshoot ultrasonic failure in Sigma Measuring Instruments?
- T
  Tiffany MartinAug 10, 2025
  If you're experiencing an ultrasonic failure with your Sigma Measuring Instruments (no signal from the sensor), begin by checking the connection between the flow meter and the sensor. Then, inspect the sensor cable for any cuts or breaks. If the connections and cable are intact, recalibrate the sensor, watching out for unusual temperature readings or the inability to read a newly calibrated level. To further isolate the issue, try using a different sensor on the same flow meter to determine if the problem lies with the instrument itself, and vice versa.
L
Lance StricklandAug 18, 2025
Why does my Sigma 980 get RS485 Time Out error?
- A
  Angela GarciaAug 18, 2025
  An RS485 Time Out error on your Sigma Measuring Instruments, indicating that the flow meter did not receive data within the specified time, can occur for several reasons. It might happen if the CPU is having trouble communicating with the velocity board; in this case, waiting a few minutes may resolve the issue. It may also be caused by difficulty getting a good velocity reading; if the logging interval is short (1 or 2 minutes), try increasing it to capture more signals. This condition may also occur occasionally when using a combination of area velocity and ultrasonic sensors, especially if site conditions are less than ideal. Finally, check the wires for shorts and inspect the RS485 fuse.
A
Andrew LopezAug 25, 2025
What to do if Sigma Measuring Instruments shows transducer ringing?
- C
  Christine WoodAug 26, 2025
  If your Sigma Measuring Instruments are showing transducer ringing, where false return echoes are masking real echoes, consider these steps: Try moving the transducer farther from the liquid. Check the area under the transducer for any obstructions, including the area in front and to the sides. Inspect the face of the transducer for any coating; cleaning it may correct the problem, and if this is a constant issue, apply a thin film of silicone grease to prevent debris from clinging. Finally, ensure that you are using the proper rubber isolation washers on the mounting bracket, as the transducer can resonate against steel mounting rails.