Коллега, их manual на стр. 36 сообщает, что:

Serial communication
The protection relay has two serial communication ports, one on the front panel and
the other on the rear panel.
The connector located on the front panel is a standard ABB optical connector that is
intended to be used for setting the parameters of the protection relay. During the
transmission of the parameters, an interface cable is connected between the relay and
the standard RS-232 interface of a PC, running the Relay Setting Tool.
On the rear panel, there is a fibre-optic interface used to connect the protection relay
to a distribution automation system via SPA, LON, IEC 60870-5-103, Modbus or
DNP 3.0 bus.
There is also an isolated RS-485 connection (twisted pair) available for SPA,
Modbus and DNP 3.0 communication in connector X3.1:9,10. For the location of
the RS-485 connection on the rear panel, see “Terminal connections” on page 57.
The connection is marked with texts “Data A” and “Data B” on the panel.

Похоже, что для параметрирования АББ используют только Передний Порт.
Задний Порт - судя по описанию, лишь для SCADA.

Позвонить в местное отделение АББ не пытались?