Engineering English
4-20 mA Current Loop
Chemical Engineering · Last updated: July 30, 2026 · How this entry was written
Definition: The 4-20 mA current loop is an analog signaling standard where a transmitter outputs a current between 4 and 20 milliamperes proportional to the measured process variable, with 4 mA representing the lower range and 20 mA the upper range.
Example in context
“All analog pressure transmitters in the plant use a 4-20 mA current loop to send the measurement signal to the PLC input card.”
“Tesisteki tüm analog basınç vericileri, ölçüm sinyalini PLC giriş kartına göndermek için 4-20 mA akım döngüsü kullanır.”
Where engineers use it
The 4-20 mA current loop is the most common analog communication method in chemical plants, used for transmitting process variables from field transmitters to input modules of controllers.
Synonyms: 4-20 mA loop, current loop
Antonyms: voltage signal
Practice: can you use “4-20 mA Current Loop” at work?
An engineer notices that a pressure transmitter output is stuck at 4 mA regardless of actual pressure; they must troubleshoot the loop for a wiring fault.
Show a model answer
“A 4-20 mA current loop transmits the process variable as a proportional current signal.”
“4-20 mA Current Loop” in 21 languages
| English | 4-20 mA Current Loop |
|---|---|
| Turkish | 4-20 mA akım döngüsü |
| French | boucle de courant 4-20 mA |
| German | 4-20 mA Stromschleife |
| Spanish | bucle de corriente de 4-20 mA |
| Chinese | 4-20 mA电流回路 |
| Arabic | حلقة تيار 4-20 مللي أمبير |
| Portuguese | laço de corrente 4-20 mA |
| Russian | токовая петля 4-20 мА |
| Japanese | 4-20 mA電流ループ |
| Italian | anello di corrente 4-20 mA |
| Vietnamese | vòng lặp dòng điện 4-20 mA |
| Hindi | 4-20 mA धारा लूप |
| Thai | ลูปกระแส 4-20 mA |
| Indonesian | loop arus 4-20 mA |
| Korean | 4-20 mA 전류 루프 |
| Bengali | 4-20 mA কারেন্ট লুপ |
| Dutch | 4-20 mA stroomlus |
| Swedish | 4-20 mA strömslinga |
| Finnish | 4-20 mA virtasilmukka |
| Ukrainian | струмова петля 4-20 мА |
Frequently asked questions
What does 4-20 mA Current Loop mean in engineering?
The 4-20 mA current loop is an analog signaling standard where a transmitter outputs a current between 4 and 20 milliamperes proportional to the measured process variable, with 4 mA representing the lower range and 20 mA the upper range. In Chemical Engineering, the term carries a usage-frequency rating of 10/10 in the Engineering English library.
How do you pronounce 4-20 mA Current Loop?
4-20 mA Current Loop is pronounced /fɔːr tə twɛnti mɪlɪˌæmpɪər ˈkɜːrənt luːp/ (IPA). The Engineering English app plays audio for the term and checks your pronunciation with speech recognition.
How is 4-20 mA Current Loop used in a sentence?
Example from an engineering context: “All analog pressure transmitters in the plant use a 4-20 mA current loop to send the measurement signal to the PLC input card.”
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