The silver utility box holds a power supply and the ADAM 6017 controller which serves as A/D converter for the three pressure transducers.  The yellow ethernet cable connects through the left side.  Cables to each of three pressure transducers connect on the bottom left.  

Also note the hooks attached to the unistrut (top center of the image).  These hooks are intended for carefully hanging the pressure regulators while changing bottles.

Power in the box is connected through a 2A fuse on the right side.  Some 110 VAC electrical contacts are open.  Lab safety rules require disconnecting power to this box before opening the cover.