4-Wire

• Meaning: A 4-wire pressure transmitter employs a configuration where two wires are dedicated to powering the device, while the other two carry the output signal. This separation ensures electrical isolation between the power supply and the signal, minimizing noise interference and improving signal quality. Additionally, many 4-wire pressure transmitters utilize a Wheatstone bridge strain gauge sensing element, which offers high accuracy and stability.  
• Specificity: The 4-wire configuration provides superior performance in terms of signal-to-noise ratio, common mode rejection, and accuracy compared to 2-wire or 3-wire transmitters. It is often used in demanding applications requiring precise pressure measurements.
• Applications:
  • High-precision applications: Suitable for processes where extremely accurate pressure readings are critical, such as in aerospace, pharmaceutical, and scientific research.
  • Noisy environments: Effective in environments with high levels of electrical interference, as the isolated signal path reduces noise pickup.
  • Long cable runs: This can be used for installations with extended cable lengths due to its improved signal integrity.

Note: While 4-wire transmitters offer superior performance, they require more wiring and can be more expensive compared to other configurations.