# Installation

## **Connecting the smart meter**

\
Connect the Dongle to the P1 connection of the smart meter via the supplied P1 cable.

## **Two hardware models**

{% hint style="warning" %}
The black model only has power on the p1 output when a usb adapter is connected. This hardware version will be delivered from May 2025.
{% endhint %}

There are two hardware types with the Modbus firmware. The white and the black one. 

The white version has a micro usb connector and fixed screw terminals. 

The back version usb c connector, P1 out and a terminal connector.

From firmware version  1.4.0 both dongle models are supported.

## **Connect USB Adapter** 

In most cases, the dongle is powered via the p1 port of the smart meter. If you have older smart meter ( v2/v3 in NL ), a USB power supply + USB cable is necessary.

{% hint style="info" %}
**Every adapter is fine**

The USB adapter may be an old smartphone or tablet adapter or a USB connection that is available in the meter cupboard (e.g. from a NAS/Router). Almost all USB adapters are suitable.
{% endhint %}

## Connect RS485

See the Modbus RTU connections below. In most cases the GND shouldn't be connected.

The wireing of the P1 Modbus Pro+ (Black casing)  is different.

<div align="center"><figure><img src="/files/f7ZTeDbqtLLweFNEq7Iq" alt="" width="375"><figcaption><p>P1 Modbus Pro dongle</p></figcaption></figure></div>

<div align="center"><figure><img src="/files/LQ09u85vRqsWOV8hp10P" alt="" width="208"><figcaption><p>P1 Modbus Pro+/NRG  (black version)</p></figcaption></figure></div>

Leds

There are two leds:

* **blue** led: flash on at startup and flashes when a P1 message is successfully read
* **green** led = power indication. Should always be on and NOT flashing.

## Button

The button has several functions:

1. Press and hold during powerup = download mode
2. short press (< 5 sec) = reboot
3. long press (>5 sec) = factory reset. All values ​​that are adjusted via the RS485 connection are reset to the default values

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