Is the QC metal chassis connected to either power supply input polarity?

Quad Cortex
1

And if not can it be? I want to use another piece of equipment to power the QC with 12 V DC, that system has the negative of the power supply connected to the grounded chassis. If both chassis are electrically connected can the QC chassis be connected to the negative power supply input?

2

The casing is connected to the centre negative of the barrel connector, though this does not electrically ground the QC’s electrical circuit.

3

Thanks for the quick reply.