You must ground the ETX-1630x rack frame as described in Pulse Current Multiplexer Attributes.

In addition, you must ground pin A16 on J9 within the adapter.

Caution Grounding pin A16 on J9 is a safety critical ground and must be capable of carrying 30 A.
Attention La broche de mise à la masse A16 sur J9 est une masse critique pour la sécurité et doit pouvoir supporter 30 A.