4-20 mA loggers wiring

Efento 4–20 mA loggers are designed to measure the output of 4–20 mA sensor probes and transmit data over NB-IoT networks to Efento Cloud or any other server. Each logger can support up to three analog channels, compatible with 2-wire probes, 3-wire PNP/NPN probes, and 4-wire probes.

The loggers can supply power (up to 16 V) to connected passive probes (2-wire, 3-wire PNP/NPN, and 4-wire). Alternatively, 2-wire, 3-wire PNP, and 4-wire probes may be powered by an external source (active mode). 3-wire NPN probes cannot be powered externally.

Efento 4–20 mA loggers measure currents within the −24 to 24 mA range, with a resolution of 0.001 mA. The shunt resistance (Rs) is 3 Ω.

Channel Configuration

Each channel can be configured for the required probe type using jumpers on the PCB:

Channel 1: Jumpers J1, J2
Channel 2: Jumpers J5, J6
Channel 3: Jumpers J3, J4

Jumper Settings

Warning! Always power off the device before changing jumper settings or wiring sensor probes.

Probe Type

Channel 1 (J1/J2)

Channel 2 (J5/J6)

Channel 3 (J3/J4)

2-wire, passive

open / closed

2-wire, active

open / open

3-wire PNP, passive

open / closed

3-wire PNP, active

open / closed

3-wire NPN, passive

closed / open

4-wire, passive

open / open

Wiring

Efento 4–20 mA loggers include a 12-input terminal block. Each terminal is labeled on the PCB (V1–V3, I1–I3, O1–O3, G1–G3), indicating both the channel number and input type. Wiring varies depending on the probe type: