One option that sets UEA slip rings apart from most others manufacturers are its custom wiring harnesses. These harnesses are built in-house to attach to either or both the center leads from the center core stack and/or the brush leads or outer portion of the slip ring assembly. Adding plugs or connectors to the outer ends of the harnesses lets the slip-ring assembly become a ‘plug and play’ component of the customer’s complete electrical wiring system.
Harnesses assembly begins with discrete wires of the correct AWG size, voltage rating, environmental rating, etc. that are often color-coded to meet a specification. The harnesses may also include or be composed of one or more jacketed cables of the required size and ratings. Discrete wires in the harnesses are ink-jet marked with the circuit number to match the correct circuit in the slip ring and often a customer specified function for that circuit. These markings are spaced about every 2 in. along the length of the wire to make the circuit easily identifiable at any position along the full length of the harness. Wires and cables are cut to a length to meet customer specified overall lengths when attached to the slip ring, bundled for use in either the brush or center harness and supplied to the Harness Layout Department. If any one of a wide variety of connector types or brands is to be attached to the harnesses, the insulation is stripped from one end of the individual wires and terminals are attached or the wires are soldered to the connectors. At that time, individual wires from the connector, or connectors if the harness includes more than one, are put through individual holes in a ‘die’ which puts the wires in the correct order to match the center core leads from the core stack of rings and insulators, or to provide a more orderly ‘break-out’ of the leads to the brushes. As the wires are pulled back through the die, they are taped to keep the wires in a correct order. A twist is often added to the harness, retained by the tape, to make the harness more flexible. Some harnesses are supplied with only the taped covering but many also add a heat-shrink tubing jacket for better sealing or an over-braided nylon thread covering for increased abrasion resistance. Completed harnesses are then attached to their slip-ring assemblies and then to a test stand for complete continuity, shorting, and other required tests. At this time point, the harnesses with connectors becomes an advantage to UEA because they are more easily attached to the test stands using mating harnesses than would be assemblies with only individual wires on the harness ends.
— Brent Jensen, Director of Engineering
United Equipment Accessories Inc.
Filed Under: News, O&M