What's the performance of the electromagnetic flowmeter?
The instruments work on the operating principle that is based on the law of electromagnetic induction of Faraday. According to this principle a voltage can be induced into a conductor that is moving in a magnetic field. The magnitude of the voltage that is induced is directly proportional to the conductor's velocity. In an electromagnetic flowmeter, the fluid works as a conductor while the sensors that contain the electrodes detect the generated voltage. The transmitter inside the flow-meter amplifies the voltage.
In order to ensure that the performance of the instruments is accurate, make sure that the electromagnetic flowmeter is grounded properly. It is quite common to see meters not grounded properly, particularly in new installations. This occurs because the unit is not referenced properly to the process. Improper grounding can also occur in existing installations too. For instance, corrosion due to the existing environmental conditions can cause immense damage to the electrical ground wiring. This enables the sensor electrodes to pick up the electrical noise, thereby affecting not just the signal to noise ratio but also the transmitter output stability.
It is important not to overlook any grounding issues as it can lead to major issues with the unit. Normally, the performance of a this instrument can be affected by three kinds of process noise that include 1/f noise, white noise and spike noise, thereby resulting in flow results that are inaccurate.