Machine Wiring — Sensor, Power and Communication

Machine wiring is the quiet layer that decides how a machine behaves in the field. Of two looms built to the same drawing, one runs for years without trouble while the other produces constant faults through a conductor broken by vibration or a mis-numbered terminal. Contech carries out internal electrical, sensor and communication wiring for machine builders and plants.

Work starts by reading the drawing. A cable schedule is produced, cross-sections and lengths are set and routes are marked out on the machine. For cables running to moving parts, drag chain use and bending radius are planned in advance; fitting a static cable on a moving axis ends in a certain break within months. Screening matters on sensor wiring. The screen must be earthed at one end only, normally at the panel; earthing both ends creates an earth loop and injects noise into the signal. Cables carrying analogue signals run on routes separate from power cables. On communication links (Profinet, EtherNet/IP, Modbus, Profibus), cable type and connector selection follow what the protocol requires, and termination resistors and segment lengths comply with the standard. Every core is numbered at both ends, matching the drawing exactly. Terminal rails are labelled. This care directly determines how long every future intervention takes once the machine is in the field; an unlabelled loom turns an hour of work into a day. On machines subject to vibration, cores are ferruled before tightening and connections are secured with locknuts or appropriate fixings. Glands are used at cable entries and protection is fitted against sharp sheet edges. When wiring is complete, continuity and insulation tests are carried out, then every input and output is verified individually. Working with machine builders in series production, the wiring standard established on the first machine is applied to all subsequent units; this shortens assembly time and makes field service predictable.