If you are running a signal cable over a long distance or have a spare current output pressure transmitter, it is possible to convert the output signal to a voltage type to make it compatible with voltage only input devices.
A typical current output is 2 wire 4 to 20 mA which is designed to be connected in a series with the power supply and other components included in the circuit. The pressure transmitter acts as a current source regulating the current at a particular pressure for a range of load impedances as long as there is sufficient supply voltage to power it.
If a load resistor is added to the circuit in series this will cause a voltage drop across the resistor which is directly proportional to the current being generated by the pressure transmitter. The potential of this voltage drop can be easily measured by connecting two voltmeter probes or an analog to digital converter to the circuit on either side of the resistor.
Featured 4-20ma current signal related products
4-20mA Output Pressure Sensors - Find reliable pressure sensors with 4-20mA current loop outputs. Designed for demanding industrial applications, offering excellent noise immunity and simplified 2-wire installation for process monitoring.
DMP331 Precision Pressure Transmitter - Stainless steel pressure transmitter with ranges from 100mbar up to 40 bar gauge or absolute. Special options for ATEX , SIL2 and compound ranges.
The voltage output generated by different values of load resistance on 4 to 20mA current loop are as follows:
| Load Resistor (Ω) | Min Volts | Max Volts |
|---|---|---|
| 50 | 0.2 | 1 |
| 100 | 0.4 | 2 |
| 150 | 0.6 | 3 |
| 200 | 0.8 | 4 |
| 250 | 1.0 | 5 |
| 300 | 1.2 | 6 |
| 350 | 1.4 | 7 |
| 400 | 1.6 | 8 |
| 450 | 1.8 | 9 |
| 500 | 2.0 | 10 |
| 550 | 2.2 | 11 |
| 600 | 2.4 | 12 |
| 650 | 2.6 | 13 |
| 700 | 2.8 | 14 |
| 750 | 3.0 | 15 |
| 800 | 3.2 | 16 |
| 850 | 3.4 | 17 |
| 900 | 3.6 | 18 |
| 950 | 3.8 | 19 |
| 1000 | 4.0 | 20 |
Alternatively use this tool to calculate the voltage drop from any 4-20mA current loop signal and load resistor value.
Featured voltage signal related products
Voltage Output DP Transducers - Differential pressure transducers with amplified 0-5V, 1-5V, 0-10V, and 1-10V outputs for precise liquid and gas DP measurement in demanding industrial and research applications. Enhanced signal clarity and 3-wire configuration.
OEM sensor for diesel tank level measurement - Submersible hydrostatic level sensor for OEM integration in diesel fuel tanks. Low-power, 0.5 to 4.5V output.
Related Help Guides
- Supply voltage and load resistance considerations for pressure transmitters
- How to Connect a 4-20mA Current Loop Pressure Transmitter
- Advantages and Disadvantages of using a 4 to 20 mA Signal
- Why use 4-20mA and 3-15 psi rather than 0-20mA & 0-15psi
- How do you measure flow rate with a dp cell
- How to get a 10 volt signal from a 4-20mA output pressure sensor
- What is the difference between a pressure transducer and a transmitter
- Choosing calibrator for pressure transmitters
- How to create a list of specification parameters for a pressure sensor
Related Technical Terms
- 2 Wire
- 4 to 20 mA Current Loop Output Signal
- HART®
- Square Root Extraction
- Stainless Steel Pressure Sensors
- Transmitter
- Turndown Ratio
Related Online Tools
- Pressure Transmitter 4-20mA Current Output Calculator
- Flow Transmitter 4-20mA Current Output Calculator
- DP Flow Transmitter Output Calculator
- 4-20mA Signal to Measurement Reading Converter
- SqRt Extraction 4-20mA Signal to Measurement Reading Converter
- Temperature Transmitter 4-20mA Current Output Calculator
- Liquid Level Transmitter 4-20mA Current Output Calculator
- 4 to 20 mA Supply, Load, Shunt and Signal Calculator