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Only use provided knockouts when feeding wires and cables into the enclosure. Any added holes in the enclosure may allow unwanted electromagnetic interference to enter the enclosure and cause unpredictable issues.
Use appropriate cable clamp connectors or metal conduit at all knockouts. This will help secure and protect wiring.
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Typically, locations such as equipment closets and factory floors are electrically noisy environments. Electrical noise, either radiated or conducted as electromagnetic interference Electromagnetic Interference (EMI), can disrupt the operation of other electrical equipment. Shielded cable is good protection against the effects of EMI.
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Cables come with various degrees of shielding and effectiveness. The amount of shielding is dependent on the environment the cable that is being used.
Levels of protection offered by shielded cable:
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The AC power wiring to the DC power supplies supply consist of the AC LINE (L), AC NEUTRAL (N), and SAFETY GROUND (G). These AC lines connected to the panel must NOT be interchanged.
Interchanging AC LINE and NEUTRAL could expose the DC power supply to the hot side of the AC supply even when the AC LINE has been switched off.
Interchanging the AC LINE and SAFETY GROUND could energize the case and cause a lethal shock.
Interchanging the AC NEUTRAL and SAFETY GROUND could cause ground currents to flow through unintended ground paths, causing unpredictable/improper system operation.
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