A 4-20mA current signal has become very popular for many applications beyond it’s original intended purpose in the process industry. It is now used throughout industry as the preferred measurement and control signal for many different types of systems.
Despite the popularity of the 4-20mA signal, it is not the best solution for every application and here are some of the ‘for’ and ‘against’ reasons for determining whether it is the right type of signal for your application.
Featured 4-20ma signal related products
200m deep well pump water level sensor, switch & display - Protect your deep well pump with thhis submersible level transmitter and wall mounted indicator and alarm. This system provides reliable water level monitoring and pump protection at depths of up to 200 meters.
Low operating temperature plus/minus 1 psi pressure transmitter - Reliable pressure measurements down to -40°C. Ideal for low range applications with a -1 to +1 psi gauge range.
Advantages
- It can be run over long distances with minimal signal losses compared to voltage type signals
- A varying current loop load impedance or supply voltage will not significantly affect the signal as long as it does not exceed recommended component limits
- Rugged signal with low electromagnetic susceptibility
- Saves on cable wire because it only needs 2 wires to function
- Live zero reading verifies sensor is electrically functional
Disadvantages
- High power consumption compared to other analogue signal types
- Elevated output at zero reading
- Supply not isolated from output
- Increasing circuit load resistance, will reduce the supply voltage available to power the transmitter that is generating the 4-20mA signal.
Featured 4-20ma signal related products
-760mmHg to +20 kg/cm² pressure transmitter with HART coms - Compound range transmitter for sensing pressure from -760 mm of mercury vacuum to 20 kilograms per sq cm positive pressure with HART communication.- Low operating temperature plus/minus 1 psi pressure transmitter - Reliable pressure measurements down to -40°C. Ideal for low range applications with a -1 to +1 psi gauge range.
Related Help Guides
- How to get a 10 volt signal from a 4-20mA output pressure sensor
- How to Connect a 4-20mA Current Loop Pressure Transmitter
- Why use 4-20mA and 3-15 psi rather than 0-20mA & 0-15psi
- Supply voltage and load resistance considerations for pressure transmitters
- Choosing calibrator for pressure transmitters
- How to create a list of specification parameters for a pressure sensor
- How do you measure flow rate with a dp cell
- Transforming a 2 wire Current Loop into a Voltage Output Signal
- 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
Related Application Questions and Answers
- 16 bar, 200°C steam pressure transmitter and gauge
- Submersible rainwater tank level sensor for measuring 3.5m depth
- Air Replacement Plant (ARP) 100 mm H2O differential pressure transmitter
- Ex rated ambient pressure sensor with 800-1100 mbar range
- HART flameproof (Ex d) re-scalable level transmitter for hydrostatic head up to 2 metres
- Dockside sea water tide level transmitter up to 6 metres depth
- Mechanical press 1000 bar pressure sensor and panel indicator
- Argon gas compatible pressure sensor for measuring up to 100 mbar
- Sulfuric acid 12-15% conc. drop-in level probe for 10m high tank
- High reading rate for measuring dynamic pressures to -200psf
- 1013 to 1400 mbar barometric pressure transmitter & readout
- 180°C UHT milk compatible pressure transmitter
Contact us about this Advantages and Disadvantages of using a 4 to 20 mA Signal page to request more information, or to discuss your application requirements.