# 4-20 mA logger

Efento 4-20 mA loggers are used to measure the output of 4-20 mA sensor probes and send the measurements over NB-IoT networks to Efento Cloud or any other server. Efento 4-20 mA loggers can be equipped with up to 3 analog channels, each of them compatible with 2-wire sensor probes, 3-wire PNP / NPN sensor probes and 4-wire sensor probes. Efento loggers can provide power supply (up to 16V) for the connected 2-wire, 3-wire PNP / NPN and 4-wire sensor probes (passive). 2-wire, 3-wire PNP and 4-wire sensor probes connected to Efento loggers can also be powered by external power source (active).

{% hint style="info" %}
**Important!** **Efento loggers can provide up to 16 V to connected 2-wire, 3-wire and 4-wire sensor probes**- **2-wire, 3-wire PNP and 4-wire probes can be also powered by an external power supply**- **3-wire NPN sensor probe can’t be powered by an external power supply**
{% endhint %}

Efento 4-20 mA loggers can measure current in \[-24; 24] mA range, with 0.001 mA resolution. Shunt resistance (R<sub>s</sub>) is 3 Ω.

## Channels configuration

Each of the logger’s channels can be configured to work with the required sensor probe type. The channel configuration is done with jumpers located on the HE9 PCB:

* Jumpers J1 and J2 - configuration of channel 1
* Jumpers J5 and J6 - configuration of channel 2
* Jumpers J3 and J4 - configuration of channel 3

| **Configuration**         | **Channel 1**         | **Channel 2**         | **Channel 3**         |
| ------------------------- | --------------------- | --------------------- | --------------------- |
| 2-wire probe, passive     | J1 - open J2 - closed | J5 - open J6 - closed | J3 - open J4 - closed |
| 2-wire probe, active      | J1 - open J2 - open   | J5 - open J6 - open   | J3 - open J4 - open   |
| 3-wire PNP probe, passive | J1 - open J2 - closed | J5 - open J6 - closed | J3 - open J4 - closed |
| 3-wire PNP probe, active  | J1 - open J2 - closed | J5 - open J6 - closed | J3 - open J4 - closed |
| 3-wire NPN probe, passive | J1 - closed J2 - open | J5 - closed J6 - open | J3 - closed J4 - open |
| 4-wire probe, passive     | J1 - open J2 - open   | J5 - open J6 - open   | J3 - open J4 - open   |

{% hint style="danger" %}
**Make sure the device is powered off when changing the jumpers settings and wiring the sensor probes!**
{% endhint %}

## Wiring scheme

Efento 4-20 mA loggers are equipped with a 12-input terminal connector. Each of the inputs is marked on the PCB (V1-V3, I1-I3, O1-O3, G1-G3), the markings indicate the input type and the channel number. The wiring scheme depends on the connected probe type.

#### 2-wire probe, powered by Efento logger (passive)

![](https://content.gitbook.com/content/GPFUI36OraG706yJS7dJ/blobs/JBCF8HFpWWPA65OXDjOV/Unknown%20image)

#### 2-wire probe, external power supply (active)

![](https://content.gitbook.com/content/GPFUI36OraG706yJS7dJ/blobs/T6FO8D8dG67ga49rSdst/Unknown%20image)

#### 3-wire PNP probe, powered by Efento logger (passive)

![](https://content.gitbook.com/content/GPFUI36OraG706yJS7dJ/blobs/3y9WAxyCMZiEoeVZBG3S/Unknown%20image)

#### 3-wire PNP probe, external power supply (active)

![](https://content.gitbook.com/content/GPFUI36OraG706yJS7dJ/blobs/otxmrEwwvVLE2tdZTqy7/Unknown%20image)

#### 3-wire NPN probe, powered by Efento logger (passive)

![](https://content.gitbook.com/content/GPFUI36OraG706yJS7dJ/blobs/dTgGjS7D5OUVvlVVEE6U/Unknown%20image)

#### 4-wire probe, powered by Efento logger (passive)

![](https://content.gitbook.com/content/GPFUI36OraG706yJS7dJ/blobs/vO9pDutLl44MFoOTC1SD/Unknown%20image)

## Calibration

Efento 4-20 mA loggers are pre-calibrated during the production and provide accurate results of the current measurements. However, if required, users can calibrate the devices to achieve higher accuracy. The calibration is performed in four points (4 mA, 12 mA, 16 mA, 20 mA), by providing the device with the known current signal from a 4-20 mA current loop calibrator. In order to calibrate 4-20 mA logger, connect to it with the mobile application -> three dots in the upper right corner -> Advanced -> Calibration.

## Startup time settings

It is possible to configure the warm-up time, in order to allow the connected sensor probe to stabilise before taking the measurement. The warm-up time is the time between providing the power to the connected sensor probe and taking the measurement. The warm-up time should be provided by the sensor probe’s manufacturer in its datasheet. In order to configure the warm-up time, connect to a logger with the mobile application -> three dots in the upper right corner -> Advanced -> Calibration -> Calibration parameters -> select the channel you want to calibrate.