Rosemount flowmeter measurement need external power supply, which makes the flow meter easily affected by electromagnetic interference, there are three kinds of methods to restrain electromagnetic interference: shielding, filtering and grounding,
1. The grounding:
In rosemount flowmeter equipment or devices, grounding is the interference in order to make the equipment or device itself produces electricity flows through the ground into the earth, and generally used in the conducted interference suppression, the ideal grounding body is a zero potential, zero impedance physical entity, as a reference point for all the signal level in the relevant circuit, no unnecessary through which an electric current produces voltage drop,
2. Block:
Very closely related to the influence of electromagnetic interference and distance, the closer from the interference source, interference field strength, the greater the influence, the greater the in rosemount flowmeter, electronic components arrangement is often restricted by volume, often with low resistance or magnetic material closed metal materials, isolating protection components or parts of the spacing is not enough, in order to reduce or prevent electrostatic or electromagnetic interference,
3. The filter:
Filtering can inhibit the transmission of electromagnetic interference, sensitive electronic equipment through telephone line and power line, the line of control, signal conduction such as electromagnetic interference signal, the low pass filter is often used to filter to conduction disturbance, can be effectively suppressed, but in the electromagnetic compatibility design, characteristics of the filter must be considered: rosemount flowmeter impedance characteristics, frequency characteristics, the rated voltage and voltage loss, leakage current, rated current, temperature, insulation resistance, reliability, appearance size, etc.,