TwinCAT 3 consists of the TwinCAT 3 development environment (TwinCAT 3 Engineering, XAE) and the TwinCAT 3 runtime environment (TwinCAT 3 Runtime, XAR).
The core of TwinCAT 3 Engineering (PLC programming) is royalty-free and can be installed on any number of development PCs. Various functions/development tools that go beyond pure PLC programming (TExxxx) as well as TwinCAT 3 runtime licenses (TCxxxx / TFxxxx) are chargeable, however.
The price of TwinCAT 3 runtime licenses depends on the performance of the control computer employed. The performance is subdivided into so-called platform levels (performance levels).
TwinCAT 3 licenses can be activated directly for a control computer. However, it is recommended to use a TwinCAT 3 license dongle.
For a current TwinCAT 3 version (from build 4022), TwinCAT 3 licenses can be ordered conveniently on a C9900-L100 license key USB stick or an EL6070 EtherCAT license key terminal and are thus ready for use immediately.
The user can add additional license files to a TwinCAT 3 license dongle at any time. A maximum of 20 license files, each with an unlimited number of licenses, are possible on a TwinCAT 3 license dongle.
The TwinCAT 3 license dongle makes the TwinCAT 3 license independent of the Industrial PC in use. The simple exchange of the Industrial PC or use of the licenses on different Industrial PCs is possible with the dongle.
The TwinCAT 3 license dongle supports a downgrade of the platform level. A license for a higher platform level can be used for all lower platform levels.
TwinCAT 3 license dongles

EL6070
TwinCAT 3.1 offers an option to manage TwinCAT software licenses via the EtherCAT Terminal EL6070. The EL6070 embodies the hardware license key in the modular EtherCAT I/O system. Data transfer takes place via EtherCAT.

EP6070-0060
TwinCAT 3.1 offers an option to manage TwinCAT software licenses directly also in distributed systems via the IP 67-protected EtherCAT Box module EP6070-0060. The EP6070-0060 embodies the hardware license key in the modular EtherCAT I/O system. Data transfer takes place via EtherCAT.

C9900-L100
As an alternative to the EL6070 license key terminal, the TwinCAT licenses can also be managed using the C9900-L100 USB stick. Data transfer takes place via USB.