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
LMP307 Submersible Level Transmitter - Submersible level transmitter for measuring liquid level with a 4-20mA current loop or a 0-10V voltage output plus optional ATEX approval for intrinsically safe use in hazardous areas in ranges from 1mH2O up to 250mH2O. The LMP307 is suitable for use on potable water with no leaching, and can be supplied with a drinking water certificate according to DVGW and KTW.
Vacuum Pressure Transmitters - Choose vacuum pressure transmitters for measurements over the low vacuum range of 25 to 760 Torr, using a absolute or negative gauge reference vacuum range.
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
IWR-5 Five Channel Wireless Sensor to 4-20mA or 1-5Vdc Output Signal Receiver - The IWR-5 is a five channel receiver designed to pair with IW series of wireless sensors and provide a 4-20mA or 1-5Vdc output signal
Hydraulic Analog Voltage Signal Pressure Transducers - Measure extreme hydraulic pressures with our robust, voltage-output (0-5V, 0-10V) transducers. Designed for actuators, presses, & pumps. Ideal for demanding applications in automotive, aviation, and material testing.
Related Help Guides
- Choosing calibrator for pressure transmitters
- Advantages and Disadvantages of using a 4 to 20 mA Signal
- How to create a list of specification parameters for a pressure sensor
- How do you measure flow rate with a dp cell
- Why use 4-20mA and 3-15 psi rather than 0-20mA & 0-15psi
- Supply voltage and load resistance considerations for pressure transmitters
- How to Connect a 4-20mA Current Loop Pressure Transmitter
- 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
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
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