The key question is what is the repetition of the power supply network (to be checked in the power grid or connection conditions attached to the contract).
this is an old type network, I don't know anything about it, but normally there are 4 links, including 3 phase ones. And the same village has the same installation. I don't want to do anything but connect this device to a 4-pin plug.
I made it quite clear what information is needed to connect. A colleague did not provide it, and an error in this matter can result in electric shock or even fire (not to mention damage to the equipment).
If a colleague bought a version with a 5-pin plug, then the socket must be the same. And to connect them, you need to know the type of mains. If you do not feel up to a colleague, please call an electrician.
I bought with 5 plugs because 4 plugs no longer produce for this type of devices and I have no humor and money to modify a few years of installation. That is why I asked how to connect an induction motor with such a switch to a 4-wire network. I do not have grounding or any differentials, the meter reaches 3 phases and N. I do not know what installation you are because I do not need life, I know that it works and no one hurt electricity.
I asked about the type of mains and gave where it can be checked. If even your friend doesn't feel like it, I suggest calling an electrician to connect the device.
If a friend does not want to replace the 5-pin socket, how does a friend want to connect the device with such a plug? Wires and adhesive tape? Will it cut the plug and replace it, which, depending on the terms of the warranty, may end in losing it? If the device connection system requires connection to a 5-pin socket, such should be used.
It is not allowed to make adapters from a 4-wire to a 5-wire installation. The socket should be replaced with a 5-pin socket and the PEN cable should be separated (or rather zero, because it probably is there). It's even cheaper.
If devices with a 4-pin plug are also to be connected to the socket, then the adapter from the 5-pin to 4-pin socket can be made without problems (unless there are devices in the "bypass" that are converted by amateurs and require a PEN cable, which is not and was not allowed).
I will buy a 5-pin plug, a piece of cable and a 4-pin socket.
So how do you combine it? Leave this plug 5x that the manufacturer gave. Replace the socket with 5 x. Now it would be best if you exchanged this piece of cable from the socket to the socket if you can for 5 x. Deriving 3 x L and PE and N separately. And if you can't do it like the subject here. https://www.elektroda.pl/rtvforum/topic423870.html Here I quickly drew how to connect this socket.