We have a new 7SJ6615-6DB00-1HA0 relay with front USB port for PC connectivity. We also have Digsi 4.94 Trial version installed on our Laptop with which we have successfully communicated with other Siprotec series relays having front Serial port with Moxa USB to serial converter. The new 7SJ66 relay firmware version is 04.33.00. The corresponding device driver for 7SJ66 V4.3 has also been installed in the Laptop.

However, when trying communication of new 7SJ66 relay with laptop through the relay's front USB port and an straight male-male USB cable, the laptop is not detecting the relay. In the device manager of the laptop ' Unknown USB device (Device Descriptor Request Failed) is displayed under USB Controllers sub heading. What could be the problem?