Yes, polarity matters. You can use that cord if you mark the wires (White GND) and (Black Hot). The reason for this is because if you happen to have 2 cords powering your equipment they would short to ground if they were reversed on 1 circuit and there were any interconnections between the 2 circuits. Besides it is to electrical code.
Fermentor 1: Bill's House Ale II, Fermentor 2: German Helles, Fermentor 3: Bill's Schworzbier (Black Bier)
Tap 1: Bill's House Ale II, Tap 2: German Hefewizen, Tap 3: Nut Brown Ale
Future Brews: Stone IPA Clone, Blonde Ale, Budvar Clone, Newcastle Clone
New toy: Blichmann 27 gallon fermentor
“If you find yourself in a hole, the first thing to do is stop digging”
“Good judgment comes from experience, and a lotta that comes from bad judgment”