Pressure transmitters are indispensable instruments that are used to measure the pressure of various mediums in industries. These devices are used for both low and high-pressure measurement application. A 2-wire pressure transmitter is a device that utilizes a two-wire configuration for both power and signal communication. It is widely used in the industry due to its simplicity, cost-effectiveness, and ease of installation. In this article, we will discuss in detail the wiring diagram of the 2-wire pressure transmitter.
What is a 2-wire pressure transmitter?
A 2-wire pressure transmitter is a device that measures pressure and converts it into an electrical signal. It has two wires, which are used for both signal transmission and power supply to the device. The device is connected to the system via two wire loops, which are used for communication with the control system. The device draws power from the control system and sends a 4-20mA signal proportional to the measured pressure.
What are the components of a 2-wire pressure transmitter?
A 2-wire pressure transmitter consists of several components, which include:
| Component | Description |
|---|---|
| Process connection | Used to connect the device to the system being measured |
| Pressure sensor | It measures the pressure and converts it to an electrical signal |
| Signal conditioning circuit | It amplifies and processes the electrical signal from the pressure sensor |
| Power supply circuit | It provides power to the device using the two-wire system |
| Output circuit | Converts the electrical signal into a 4-20mA signal proportional to the pressure measured |
Wiring diagram of a 2-wire pressure transmitter
The wiring diagram of a 2-wire pressure transmitter is quite simple. The device is connected to the control system using two wires, which are used for both signal communication and power supply. The two wires are connected to the power supply circuit and the output circuit of the device.
Wiring diagram of a 2-wire pressure transmitter with a PLC
When using a programmable logic controller (PLC), the wiring diagram of a 2-wire pressure transmitter is slightly different. In this configuration, the device is connected to the PLC using two wires, which are used for signal communication only. The power supply to the device is provided by the PLC via the same two-wire configuration.
The wiring diagram of a 2-wire pressure transmitter with a PLC is shown below:
| Device | Wire color | Connection to PLC |
|---|---|---|
| 2-wire pressure transmitter | Red | Terminal A of analog input module |
| 2-wire pressure transmitter | Black | Terminal B of analog input module |
FAQs
What is the purpose of using a 2-wire pressure transmitter?
The purpose of using a 2-wire pressure transmitter is to measure the pressure of various mediums in industries. It is a simple, cost-effective, and easy-to-install device that uses only two wires for both power supply and signal communication.
What is the difference between a 2-wire and a 4-wire pressure transmitter?
The main difference between a 2-wire and a 4-wire pressure transmitter is the number of wires used for power supply and signal communication. A 2-wire pressure transmitter uses only two wires for both power supply and signal transmission, while a 4-wire pressure transmitter uses four wires; two wires for power supply and two for signal communication.
How accurate are 2-wire pressure transmitters?
The accuracy of a 2-wire pressure transmitter depends on several factors, such as the quality of the device, the calibration process, and the measurement environment. However, most 2-wire pressure transmitters have an accuracy range of +/- 0.5% to +/- 1% of the full-scale measurement range.
Can a 2-wire pressure transmitter be used in hazardous areas?
Yes, a 2-wire pressure transmitter can be used in hazardous areas, but it requires proper certification and installation. The device should be certified according to the safety standards of the hazardous area and properly installed by a qualified professional.
