GE PT878 user manual Wetted Transducer Problems

Chapter 9. Diagnostics and Troubleshooting

9.4 Transducer Problems

Ultrasonic transducers are rugged. However, they are subject to physical damage due to mishandling and chemical attack. Clamp-on transducers are also subject to installation variables such as physical misalignment and faulty coupling to the pipe on which they are mounted.

Because transducer problems are largely dependent on the type of transducer used, wetted or clamp-on, the following list of potential problems is grouped according to transducer type. Contact the factory if you cannot solve a transducer-related problem.

9.4.1 Wetted Transducer Problems

1.LEAKS

Leaks may occur around the transducer and in the fittings of the flow cell. Repair as you would any other leak. Check the transducer and cables for damage if the leaking fluid is corrosive.

2.CORROSION DAMAGE

Wetted transducers may be damaged by corrosive fluids if the transducer material does not match the application. Most often, corrosion damage occurs at the electrical connector. To check for damage, remove the transducer from the flow cell. If the wetted end of the transducer is rough and pitted, the transducer may have to be replaced. GE can supply suitable transducer materials for most fluids. Contact the factory for information on special transducers.

3.INTERNAL DAMAGE

An ultrasonic transducer consists of a ceramic “crystal” bonded to the transducer case. The bond between the crystal and the case may be damaged by extreme mechanical shock and by temperature extremes. The crystal itself can also be damaged by the same conditions. The internal wiring can be corroded or shorted if contaminants enter the transducer housing.

210 Transport® Model PT878 Portable Liquid Flowmeter User’s Manual