Flow · Measurement
Magnetic & Ultrasonic Meters
Meters with nothing in the flow path. A magnetic meter reads the voltage a conductive liquid makes in a magnetic field; an ultrasonic meter times sound pulses across the pipe.
What it does
Measure produced water and water injection with no pressure drop and no moving parts. Ultrasonic meters also come in clamp on versions and in multipath versions for gas.
Basics
| Magnetic | Conductive liquids only, so water, not oil or gas |
| Ultrasonic | Liquids, and gas with multipath meters |
| Gas ultrasonic standard | AGA Report No. 9 |
| Needs | Full pipe, some straight run |
Common failures
- Magnetic meter on oil, it cannot read
- Partly full pipe or gas pockets
Troubleshooting
- Symptom
- Magnetic meter reads zero or noise
- Likely cause
- Low conductivity or electrodes coated
- What to check
- Confirm the fluid is water, clean the electrodes, check grounding