Category Archives: 4-20 mA Current Loop

How To Power Multiple 4-20 mA Sensors

Data Logger > 4-20mA Process Current We’re often asked how to power multiple 4-20 mA sensors using a single power supply. While it is possible to do this, the usual cautions apply regarding ground loops and other subtleties. Readers who are new to measurements using sensors with 4-20 mA process current outputs should refer to our Read More

4-20 mA Measurement Resolution

Data Acquisition > 4-20mA Current Loop Don’t overlook a vital component that affects 4-20 mA measurement success: Measurement resolution. Measurements from sensors that have a 4-20 mA output are very common. Customers always ask how to connect them to a data logger or data acquisition system, which we describe in detail here. However, they often overlook a vital Read More

How To Measure Current

Data Acquisition > 4-20mA Current Loop …current is always measured indirectly from an external sensor that produces a voltage output that is proportional to current. Since the only difference between a voltage and current measurement is the scaling that you apply to the result, voltage measuring instruments are almost always used to measure current.   Read More

How To Determine 4-20 mA Loop Load

Data Acquisition > Current Process current (4-20 mA) measurements are popular with DATAQ Instruments’ customers, and that often leads to some interesting application questions. One of the better ones relates to how many process current instruments can be connected to a single current loop. Customers know that there MUST be a limit, but they’re not Read More

4-20 mA Current Loop Data Acquisition

Data Acquisition > Current One of the most common industrial measurements is 4-20 mA current loop data acquisition. Electrical noise, present in most industrial settings, makes measuring a sensor/transducer output as a voltage impractical—especially over long distances. The solution is to transmit the sensor/transducer output as a current signal (process current). This is achieved by Read More

How To Make 4-20 mA Current Loop Measurements

Data Acquisition > Current Additional Reading: 4-20 mA Current Loop Data Logger Products 4-20 mA Current Loop Data Acquisition Products It seems that at least one 4-20 mA (milliamp) measurement is required by our typical customer, and the way to do it is a constant source of confusion for many. So I thought I’d zero Read More

4-20 mA Current Loop Measurement Resolution Calculations Made Easy

Data Acquisition > Current I estimate that 20-30 percent of measurements made by our customers are from 4-20 mA current loop sensors and systems. If you draw a blank after reading this first sentence, see this and this for some 4-20 mA background information. One question that arises quite often is how to calculate measurement Read More