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Especially the power cord as it does not have a locking mechanism that RJ45 has.

How to safely break the connection between the dongle and the pay terminal

To more easily restart the terminal and/or disconnect the terminal from the computer, you may break the connection on the cord between the pay terminal and the dongle.

If you follow the cord from the pay terminal, after around 20 centimeters from the terminal

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you find this square formed connection, which you can open by putting your fingerlail under the ledge and pressing up: