Hi Rhfil
I haven't done it but Märklin did. See the video below.
Key principles
- one router modem is used to connect both CS3 by a CAT5 or CAT6 Cable and set in DHCP mode (automatic address assignation)
- one of the CS3 msut be a SLAVE and ONLY a CS3PLUS can be used while being a master can be made with ANY CS3 type
- a cable 60123 must be used to link the CS3 Master with the CS3 Slave

- a soon as to tell a CS3+ it is a slave, it reboots and connects with the master to import date from the master


The video (sorry in German)

TRhe screen in 1:35 shows how to declare a unit as a slave ("Zweitgerät")
In 2:37, one CS3 (Master) and one CS3+ (slave) are shown and how the connection is done

I hope this helps
Cheers
Jean

The most fundamental answer is to just swap out the CS2 and place the CS3 in its place,
As long as the power to the CS2 was a Power Supply and not a Transformer, you can reuse that power supply for the CS3

This presumes you are already using a 60123 cable with the 6 pin end at the CS3+ and the 9 pin at the CS2
If you have the cable the other way around, you will need to swap it end-for-end as the CS3(60226) does not have the 6-pin socket.

You do not NEED the network cable, if you have the 60123 cable between the units.
However there are a few "admin" type functions, like the transfer or images that benefit from this connection.

CONERSELY, the CS3s may be connected together with ONLY a network cable

This brings up the need for you to explain "why" you are "replacing" the CS2.
Personally I do not see a need to get rid of the CS2 and would continue to use it as a "back room worker"

A "network only" connected CS3 , does loose the ability to drive "power to the track",
however if you are primarily using this for its throttles or layout track boards this is fine.

Edited by user 23 March 2025 09:18:35(UTC)  | Reason: Not specified