Kakadu with Selectronic SP PRO SPLC1202 & AERL CoolMax SRX

AERL Kakadu · Commissioning Guide

Commissioning Guide Rev 1.1.6 8 Nov 2026

Introduction

This guide covers the system-level commissioning of a Kakadu 120 battery bank operating with Selectronic SP PRO SPLC1202 inverters and AERL CoolMax SRX 120 DC-coupled MPPT charge controllers. It sets out AERL's recommended control philosophy, the hardware required, how the communications are connected, and the settings to program into the Nexus and the SP PRO.

It does not replace the product manuals. Install each item in accordance with its own documentation first.

Reference Documents

Who may commission this system

Installation, termination and commissioning must be carried out only by a licensed electrical worker competent in battery energy storage systems, in accordance with AS/NZS 3000 and AS/NZS 5139.

What has changed

Since Rev 1.0.0 the SP PRO runs the Kakadu as a managed battery (battery type BMS – SelectCell River Gum); the Rev 1.0.0 Custom battery settings and SP LINK configuration file no longer apply. Cables made to Rev 1.1.5 or earlier used the wrong BMS-end CAN pins (now 4 and 5, section 3.4) — check them.

AERL Kakadu · Commissioning Guide

Commissioning Guide Rev 1.1.6 8 Nov 2026

Control Philosophy

AERL recommends the following control philosophy for the Kakadu battery.

• The AERL Nexus Gateway is the EMS for the entire system.
• The Kakadu is a managed battery. Its master BMS broadcasts the battery's safe operating window over CAN bus.
• The SP PRO SPLC1202 runs the Kakadu as a managed battery, with SP LINK battery type BMS – SelectCell River Gum. It reads the Kakadu's CAN data directly, and the SelectCell River Gum profile applies the correct voltage and charge settings.
• The Nexus monitors the SP PRO and sends target charge control points to the CoolMax SRX.
• The CoolMax SRX charges from solar to the target charge control points set by the Nexus.

AERL Kakadu · Commissioning Guide

Commissioning Guide Rev 1.1.6 8 Nov 2026

Roles

State of Charge

With a managed battery type, the SP PRO takes the battery SoC directly from the Kakadu BMS. No SP PRO DC shunt is needed on the SRX output.

AERL Kakadu · Commissioning Guide

Commissioning Guide Rev 1.1.6 8 Nov 2026

Required Hardware

2.1 Bill of Materials

2.2 SP PRO Prerequisites

Check the following in SP LINK under Data View → Inverter Details before you connect the Nexus.

EMS firmware

The Nexus Gateway and every CoolMax SRX must run AERL's EMS firmware for this control philosophy. AERL installs it remotely during commissioning (section 4.1.2).

AERL Kakadu · Commissioning Guide

Commissioning Guide Rev 1.1.6 8 Nov 2026

Connections

Two communication links make up the control system.

• CAN bus (CAN 2.0A): SP PRO → Nexus → CoolMax SRX → Kakadu
• RS485 (Modbus RTU): Nexus → SP PRO, for monitoring

3.1 Rules for the Communications Wiring

1. One CAN bus. The Kakadu, the SRX units, the Nexus and the SP PRO share a single CAN bus. Its order is SP PRO → Nexus → SRX → Kakadu.
2. CAN bus termination. The two ends of the bus are the SP PRO and the Kakadu master BMS, and each needs 120 Ω termination. Nothing in between should be terminated.

   Device	Position on the bus	Termination setting
   SP PRO (PowerChain master)	End	CAN termination DIP switch on the comms card ON
   AERL Nexus Gateway	Mid-bus	None (no built-in termination; at a bus end, fit a 120 Ω plug in its spare CAN socket)
   CoolMax SRX (every unit)	Mid-bus	CANBUS 120 Ω switch OFF
   Kakadu master BMS	End	Automatic — nothing to set

AERL Kakadu · Commissioning Guide

Commissioning Guide Rev 1.1.6 8 Nov 2026

3. Master BMS. The BMS whose INV port connects to the CAN bus is the master. Leave its Master Unit LED lit and turn it off on every other BMS. Leave Last Unit lit on the final string in the chain only (Kakadu 120 manual §6.3 and §6.4).
4. PowerChain master only. On a PowerChain system, connect the CAN bus and the RS485 lead to the PowerChain master only. The other inverters receive battery data over Selectronic's PowerChain link.
5. Cabling practice. Mount the Nexus as close as possible to the SP PRO, so that the RS485 run is short. Use shielded CAT5e/CAT6 for CAN, with the shield earthed at one end only. Keep comms cables separated from DC power runs. Contact AERL for any CAN run longer than about 100 m.

3.2 Simple System — 1 × Nexus, 1 × SPLC1202, 1 × CoolMax SRX

AERL Kakadu · Commissioning Guide

Commissioning Guide Rev 1.1.6 8 Nov 2026

3.3 Multi-cabinet Example — 4 × Kakadu, 4 × SRX, 3 × SPLC1202

3.4 SP PRO to BMS Cable

The SP PRO and the Kakadu BMS use different RJ45 pins for CAN. Connect the SP PRO to the CAN bus with the SP PRO to BMS cable, which re-maps the pins. A standard straight-through patch lead will not work.

Plug the SP PRO end into the SP PRO CAN socket (the PowerChain master on a PowerChain system). Plug the BMS end into Nexus CAN 2.

AERL Kakadu · Commissioning Guide

Commissioning Guide Rev 1.1.6 8 Nov 2026

Pins 1/2 at each end cross to pins 4/5 at the other end, as shown in Selectronic's BMS to SP PRO CAN Bus cable application note. The cable is symmetrical and works either way round. CAN_H / CAN_L are on pins 1 / 2 at the SP PRO and on pins 4 / 5 at the Nexus CAN 2 socket.

If you make the cable up yourself, keep CAN_H and CAN_L on one twisted pair, and check every pin for continuity against the table before you fit it.

AERL Kakadu · Commissioning Guide

Commissioning Guide Rev 1.1.6 8 Nov 2026

Set-Up

4.1 AERL Nexus Gateway

4.1.1 Set up the Nexus as normal

Follow the AERL Nexus installer guide Selectronic SP PRO → AERL Cloud (Rev 1.0.1). In summary:

1. Connect the Nexus RS485 socket to SP PRO ACC Port 1 with a straight-through CAT5e/CAT6 patch lead.
2. Connect the CAN bus as described in Chapter 03.
3. Connect Ethernet from the site router, then power the Nexus on. It connects to AERL Cloud automatically.
4. At aerl.cloud, click Add Gateway on the Gateways page (or + in the top bar). On Claim Your Gateway, enter the serial number and pin code from the Nexus label and click Claim Gateway, then assign the gateway to a location.
5. In Gateways, choose Manage on your Nexus to open Edit Gateway, then Modbus Devices → Add Device; set Device Product to Selectronic SP PRO and click Add Device. You need the Owner or Admin role. The configuration applies within about five minutes.

The Kakadu BMS and the CoolMax SRX units on the CAN bus are discovered automatically.

4.1.2 EMS firmware push — contact AERL

Once the Nexus is online and claimed, contact AERL technical support to push the EMS firmware to the Nexus and the CoolMax SRX units. Have the following ready:

• the Nexus serial number
• the serial number of every CoolMax SRX
• the number of Kakadu cabinets, and the SP PRO configuration (single inverter or PowerChain)
• the site name and location as claimed in AERL Cloud.

AERL confirms when the push is complete. Then check in AERL Cloud that the Kakadu and every SRX are reporting.

AERL Kakadu · Commissioning Guide

Commissioning Guide Rev 1.1.6 8 Nov 2026

4.2 Setting up the CoolMax SRX

Set up every CoolMax SRX on the site with AERL Link:

1. Download and install the latest version of AERL Link, then connect to the SRX.
2. Change the preset to Kakadu.
3. Change the Battery Type to Kakadu.
4. Check that the charge settings match Figure 4.1, then save the settings to the SRX.

Also set the CANBUS 120 Ω switch on every SRX to OFF (section 3.1).

4.3 SP PRO — System → Communication (Modbus to the Nexus)

Setting	Value
Port 1 Baud Rate	57600
Port 1 DTR/DCD	Enabled
Port 1 Comm Card Input	Internal (RJ45)
Port 2 Baud Rate	9600
Port 2 DTR/DCD	Enabled
Modbus RTU Port	9600 · 8 bit · None · 1 stop
Modbus RTU Address	1

These Modbus settings must match what the Nexus expects: slave 1, 9600 baud, 8N1.

AERL Kakadu · Commissioning Guide

Commissioning Guide Rev 1.1.6 8 Nov 2026

4.4 Save, Upload and Site-Specific Settings

1. Confirm the SP LINK Battery Type is BMS – SelectCell River Gum (Figure 4.3).
2. Save the configuration and upload it to the SP PRO.
3. In SP LINK, open Data View → Battery Management and confirm that the Kakadu BMS data is shown. This view is only available with a managed battery.
4. Confirm in AERL Cloud that SP PRO data appears on the Nexus within about five minutes.

Site-specific parameters

Installers must set up all other parameters as required for their site. These include unit application, nominal AC voltage and frequency, AC source power, generator controller settings, generator schedule start, AC input, power quality / DRM, inputs and outputs, and PowerChain settings.

4.5 Final Checks

AERL Kakadu · Commissioning Guide

Commissioning Guide Rev 1.1.6 8 Nov 2026

AERL Technical Support

When You Contact AERL, Include

• the site name, and the Nexus serial number
• the serial numbers of the CoolMax SRX units, and the number of Kakadu cabinets
• the SP LINK Inverter Details and Battery Management screenshots, and the exported SP LINK configuration file
• a short description of what you see, including the Nexus Tx/Rx LEDs if the issue is with RS485 comms.