APC Easy UPS is not detected by QNAP NAS

[Emil2]

Hello all, I hope somebody can help me I have a bit of a tricky issue. 

I recently purchased an APC Easy UPS On-Line SRV (Model SRV1KRIRK) to protect my NAS (QNAP TVS-473). I connected the UPS to the NAS with the USB cable but the NAS did not recognize the UPS. After some research I came across a list of QNAP in which the supported UPS are listed unfortunately mine was not there. Now I would like to set up the UPS so that I can connect my NAS either via SNMP Connection with the UPS or as a Network UPS slave. I have written to the support of APC but they have helped me only partially they said that only the SRVSMB001 (A smart card from APC) is compatible with this UPS. I have read the instructions for this card and do not understand what I have to do. In this manual they talk about converters from RS-485 to TCP and so on. The card has LAN cable ports but when I search for such a converter on the internet I only find converters with one serial and one LAN port.

My question now can someone tell me how I can make it so that the UPS is recognized by the NAS no matter how and if I have to buy this card what exactly I still need to set up the Network UPS Slave or SNMP.

Or if I can change something on the NAS that the UPS is recognized?
Another solution is of course also very welcome.

Reference: 

My UPS: https://www.apc.com/de/de/product/SRV1KRIRK/apc-easy-ups-online-srv-rackmount-1000-va-230-v-mit-schi...

Smartcard: https://www.apc.com/de/de/product/SRVSMB001/easy-ups-online-srvs-modbus-karte/

My QNAP NAS: https://www.qnap.com/en/product/tvs-473

QNAP supported UPS: https://www.qnap.com/en/compatibility/?model=254&category=9

Smarcard Guide: https://download.schneider-electric.com/files?p_Doc_Ref=SPD_AHUG-BEC93C_EN&p_enDocType=User+guide&p_...