Worked on cable installation in electronics room racks ISC-C3 and ISC-C4. While powering up electronics in ISC-C4, connected ±18V backwards to either:

D1002735 Harmonics Generator Power Supply - SN S1000791 or
D1000124 RF Distribution Amplifier - SN S1000604

Units seem to be powering up, but will look closer once testing begins.

Filiberto Clara