Visonic Powermax pro and Homey

I have been struggling for weeks to connect Homey to my Powermax pro.
I have connected a USR-TCP232-E2 to my network and to the PC/IP connector of the powermax. I have a separate 5V power supply connected to the USR. And connected the TX, RX and GND of the USR to pins 3, 5 and 7 of the PC/IP connector of the Powermax pro.
The usr is set to TCP server, 8,1,n and 9600 baud and has a fixed ip that can be found on my local network.

In order to get homey to find the powermax panel you have to put the power link option in the powermax Pro in learning mode. However when I try to find the power link learning option than it is not present in the user menus of the powermax pro.

Is the missing PWRlink option maybe the result of not detecting the USR because of wrong wiring? Anyway, I am stuck.

Can somebody point me in the right way?

The issue is solved. I made a mistake in the wiring. Thank you Robert Lunden for publishing a how to manual!