Current Loop Connection - Dent ELITEpro XC Operator's Manual

Current Loop Connection

Sensors using current loops are widely used in industry to communicate analog signals in the presence
of electromagnetic interference. Both 2- and 3-wire current loops (often referred to as loop powered or
separately excited, respectively) are commonly used in industry. Both types of current sensors are
illustrated in this section. Internally, the ELITEpro XC uses 0.1% precision 499 ohm resistors to measure
the voltage drop impressed by the external current source. Current loop sensors will typically be
powered from a 24-volt DC supply. The ELITEpro XC has four measurement channels. The negative
terminals of each channel are common to each other and connected to the reference plane for power
measurements. For this reason it is imperative that the ELITEpro XC be connected as the last component
in the current loop rather than the first if multiple channels are used. Best practices are to use a single
power supply for all sensors to reduce the occurrence of ground loop current between supplies.
G
L2
DENT Instruments
ELITEpro
+
-
Power Supply
L1
2-Wire Current Loop Configuration
Prepping & Using the ELITEpro
Sensor
28