DC 4~20mA Pressure Transmitter

DC 4~20mA Pressure Transmitter

Introduction:

A DC 4-20mA pressure transmitter is a type of sensor used to measure pressure and convert it into an electrical signal that can be easily transmitted and interpreted by control systems and instrumentation. The 4-20mA signal is a common industry standard for transmitting process variables.

Here's how it works:

1. Pressure Sensing: The pressure transmitter consists of a pressure sensor or a sensing element, such as a piezoresistive or capacitive element. When pressure is applied to the sensing element, it undergoes physical changes, which are converted into an electrical signal proportional to the pressure.

2. Signal Conditioning: The raw signal from the pressure sensor is usually very small and requires amplification and conditioning. Signal conditioning circuitry is built into the transmitter to amplify and scale the signal to the desired range.

3. Output Signal: The transmitter's output signal is typically a direct current (DC) signal, where the current value represents the measured pressure. In the case of a 4-20mA transmitter, the output current ranges from 4mA to 20mA, corresponding to the pressure range being measured.

• 4mA represents the lower end of the pressure range, often set to zero pressure or the minimum value.
• 20mA represents the upper end of the pressure range, corresponding to the maximum pressure that the transmitter can measure.

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