Instrumentation Cable

Industrial applications such as factory floor are typically electrically noisy environments. Electrical noise either radiated or conducted as electromagnetic interference (EMI), can seriously disrupt the proper operation of other equipment. Shielding is needed to combat the effects of EMI. The shield can act on EMI on two ways. First it can reflect the energy. Second, it can pick up the noise and conduct it to ground. In either case, EMI does not reach the conductors.

There are two types of shielding typically used for cables namely, foil and braid. Foil shielding uses a thin layer of aluminum, typically attached to a carrier such as polyester to add strength and ruggedness, which is good. A drain wire is used to terminate and ground the shield.

Braid is a woven mesh of bare or tinned copper wires. The braid provides a low resistance path to ground and is much easier to termination by crimping or soldering when attaching a connector. The braid is more effective as a shield.