Selectronic SP PRO → AERL Cloud

AERL Nexus · SP PRO Setup

Installer Guide Rev 1.0.2 09 November 2026

Confirm the SP PRO Supports Modbus

Open SP LINK, connect to the inverter, and perform the following checks.

Inverter Details Checks

Go to Data View → Inverter Details and confirm all of the following:

Then physically locate the RJ45 socket on the SP PRO comms card labelled Port 1.

AERL Nexus · SP PRO Setup

Installer Guide Rev 1.0.2 09 November 2026

Wiring and Switching on Modbus

The Cable

The SP PRO and the Nexus use the same RJ45 wiring layout, so a normal straight-through CAT5e or CAT6 patch lead is required. Plug one end into Port 1 on the Selectronic ACC and the other into the Nexus's RS485 socket.

Keep the run short

Ensure the Nexus is installed as close as possible to the SP PRO.

Turning Modbus On

The SP PRO ships with Modbus switched off. To enable it in SP LINK:

1. Go to Configuration Settings → System → Communication.
2. Set the serial parameters — these must match what the Nexus expects:
   • Comm Card Input: Internal (RJ45)
   • Modbus Address: 1
   • Baud rate: 9600
   • Modbus port: 8 data bits, 1 stop bit, no parity (written as 8 bit, None 1 stop)
3. Save and upload the new config to the SP PRO.

PowerChain systems

On a PowerChain system, the connection and setting should be done on the PowerChain master.

AERL Nexus · SP PRO Setup

Installer Guide Rev 1.0.2 09 November 2026

Getting the Nexus Online

Plug It in and Get It Online

1. Connect the Nexus's RS485 port to the SP PRO if not already done.
2. Plug an Ethernet cable into the Nexus's network port from your internet router.
3. Power the Nexus on.

As soon as the Nexus detects the Ethernet link, it automatically connects to AERL Cloud.

If Ethernet isn't available

Contact AERL for support with a Wi-Fi setup.

Linking the Nexus to Your AERL Cloud Account

In a new browser tab, open https://aerl.cloud, then:

1. Sign in. If you don't have an organisation set up yet, create one for the site.
2. Click Add Gateway on the dashboard or the Gateways page (or the + button in the top bar).
3. On Claim Your Gateway, enter the serial number and pin code from the sticker on the Nexus, then click Claim Gateway. AERL Cloud adds the gateway to your organisation.
4. Assign the gateway to a location — pick an existing one or create a new one with the site address and coordinates.

Providing Customer Access

To give the customer access, go to Organisation → Invitations and invite them.

Wrong account claimed

If a gateway has been claimed by the wrong account by mistake, contact AERL support.

AERL Nexus · SP PRO Setup

Installer Guide Rev 1.0.2 09 November 2026

Adding the SP PRO in AERL Cloud

Add the Inverter as a Modbus Device

You need the Owner or Admin role in the organisation. In the AERL Cloud web app, go to Gateways and click Manage beside your Nexus. In Edit Gateway, under Modbus Devices, click Add Device.

1. Device Product: pick Selectronic SP PRO from the dropdown.
2. Click Add Device. The Nexus is automatically configured to connect to the SP PRO via its RS485 port.

The Nexus should download new config from the cloud within about five minutes. You don't need to restart the device.

Make sure the SP PRO's Modbus settings in SP LINK (slave 1, 9600, 8N1 — see Chapter 02) match the defaults the Nexus expects.

Sole master on the comms link

The Nexus Gateway does not support other Modbus master devices on the comms link with the SP PRO.

Confirming Data Is Being Received

Within about five minutes of saving, inverter data should start appearing in the gateway view. You'll see readings grouped as:

How often data is sent depends on how the Nexus connects to the internet. The Nexus automatically determines which type of connection it has. It sends data every minute when connected via Ethernet and every ten minutes via cellular.

AERL Nexus · SP PRO Setup

Installer Guide Rev 1.0.2 09 November 2026

Troubleshooting

More detailed help

Refer to the SP PRO Manual, §4.3.1 for more detailed troubleshooting.

The Nexus has two status LEDs next to its RS485 socket, labelled Tx and Rx. Tx flickers when the Nexus sends a Modbus request; Rx flickers when the SP PRO replies. Use these LEDs (on the Nexus, not the SP PRO) to diagnose the link.

When to Involve AERL Support

If the LED test looks healthy but data still isn't flowing, AERL support can run a bus-discovery check on the Nexus from our end. That separates “is the electrical connection working” from “is the cloud configuration right”. When you raise a ticket, give us the Nexus serial number and a quick note on what the LEDs are doing.

No Support for Multiple Modbus Masters

The Nexus expects to be the only device polling the SP PRO. If there is another Modbus master on the same wires (another gateway, a data logger, or a remote screen interface), the devices will interfere with each other. Connect the other device to another comms card or inverter.

AERL Nexus · SP PRO Setup

Installer Guide Rev 1.0.2 09 November 2026

Managed Batteries & Final Checklist

CAN Bus and Managed Batteries

Some installations also have a battery management system talking to the SP PRO over CAN bus. The Nexus automatically supports managed batteries over CAN bus; there is nothing to set up. If you connect the Nexus to that bus, CAN 1 and CAN 2 are linked internally, so it can sit inline. The Nexus has no built-in termination: if it is at an end of the bus, fit a 120 Ω RJ45 termination plug in its unused CAN socket.

Random comms dropouts

Ensure the Nexus is on the latest firmware before raising a ticket.

Quick Commissioning Checklist

1. Confirm the SP PRO is suitable: ACC Rev 8 or higher, firmware V14.47 and V4.31 or newer, Series 2i.
2. Run a CAT5e or CAT6 patch lead from the SP PRO's ACC Port 1 to the Nexus's RS485 socket.
3. In SP LINK, turn on Modbus. Slave 1, 9600 baud, 8N1.
4. Plug an Ethernet cable into the Nexus and power it on.
5. Claim the gateway in AERL Cloud using the serial number and pin code from the sticker.
6. Add the Modbus device: pick Selectronic SP PRO as the Device Product and click Add Device.
7. Wait five minutes. Data should appear.

Getting Help