Troubleshooting Current Loops with Voltage Measurement
Sometimes ammeter or current measurement with multimeter is unavailable at work locations , we can still perform useful troubleshooting measurements
how 4-20ma loop works
Basics of 4 to 20 mA analog Signals
The  most  popular  form of signal transmission  used in modern  industrial  instrumentation  systems is the 4 to 20 milliamp DC
