---
title: "How could I add a new xtender in a multi-unit system without conflicts?"
description: "When you add a new unit to a multi-unit system or when a repaired unit is back. You must be aware that they could have a different SW version and a different configuration. In order to avoid conflicts, before starting…"
url: "https://studer-innotec.com/support/faq/xtender-inverter-chargers-series/configuration/how-could-i-add-a-new-xtender-in-a-multi-unit-system-without-conflicts/"
updated: "2026-06-25"
category: Configuration
tags:
  - phases configuration
  - xtender xth inverter
  - xtender xtm inverter
  - xtender xts inverter
---

# How could I add a new xtender in a multi-unit system without conflicts?

When you add a new unit to a multi-unit system or when a repaired unit is back. You must be aware that they could have a different SW version and a different configuration.

In order to avoid conflicts, before starting the system, you must follow this procedure:

Save all files from the old units to the SD card when disconnected from the new one (rcc settings/save and restore/save all files {5041}).

![rcc screenshot](https://studer-innotec.com/wp-content/uploads/2024/08/download-36.png)

 

- Install physically:
  - Electrical Wiring: communication cables in Studer bus. The positions of the devices is important (xt, vt and vs in the middle and accessories at the ends of the bus).
  - ![rcc screenshot](https://studer-innotec.com/wp-content/uploads/2024/08/download-37.png)
  - Termination bus switch. If the inverter is situated at the end of the communication bus the switch must be adjusted in "T" position. If not it should be adjusted in "O" position (Images below show switch location). 
     ![xtender xth](https://studer-innotec.com/wp-content/uploads/2024/08/download-38.png)![xtender xtm](https://studer-innotec.com/wp-content/uploads/2024/08/download-39.png)![xtender xts](https://studer-innotec.com/wp-content/uploads/2024/08/download-40.png)
  - Phase Selection jumper. change the jumper to indicate to the new inverter in which phase it will be located. Adjust in L1, L2 or L3 (Images below show jumper location).
     ![xtender xth](https://studer-innotec.com/wp-content/uploads/2024/08/download-41.png)![xtm xtender](https://studer-innotec.com/wp-content/uploads/2024/08/download-42.png)![rcc screenshot](https://studer-innotec.com/wp-content/uploads/2024/08/download-43.png)
  - Update the software to the latest version. 
  - Apply configuration files (rcc settings/save and restore/apply configuration files (Masterfile) {5070}) that have been created on SD card during point 1.
     ![rcc screenshot](https://studer-innotec.com/wp-content/uploads/2024/08/download-44.png)
  - Start the system

In the rcc you only see the settings from the master, not from all units, so it is always better to apply settings using the master so all units have the same configuration.