{"id":195,"date":"2022-04-28T17:14:42","date_gmt":"2022-04-28T21:14:42","guid":{"rendered":"https:\/\/opentextbc.ca\/plumbing3f\/chapter\/describe-wiring-components\/"},"modified":"2022-08-10T16:32:00","modified_gmt":"2022-08-10T20:32:00","slug":"describe-wiring-components","status":"publish","type":"chapter","link":"https:\/\/opentextbc.ca\/plumbing3f\/chapter\/describe-wiring-components\/","title":{"raw":"Learning Task 1","rendered":"Learning Task 1"},"content":{"raw":"If the designer has also produced a schematic or a ladder diagram for the wiring and controls, all that is left is the physical installation of the electrical components. This is where installers have had, and continue to have, issues. Those issues revolve around the parts, pieces and installation techniques required by the installer to ensure that this part of the system is completed properly. We\u2019ll look at some of the things that come into play when wiring hydronic systems.\n

\"Field Wiring\"<\/h1>\nThe wiring that we, the installers, are responsible for is commonly shown on manufacturers\u2019 literature and labeled as \u201cfield wiring\u201d. This is any wiring that is not pre-installed on the equipment at the factory. In a forced air furnace installation, the field wiring is usually limited to the wiring for the thermostat and the connection of the line voltage power supply. There is much more field wiring needed for hot water heating systems. The legal ability for pipe trades personnel to perform any field wiring of a hydronic heating system, regardless of voltage, falls under a Gasfitter \u201cA\u201d or \u201cB\u201d Certificate of Qualification, as long as the fitter is working under a gas contractor\u2019s license, an installation permit has been obtained and the heat source is gas-fired. Most in the hydronics industry would agree that a plumber\/gasfitter, rather than an electrician, should logically be the person to perform this work due to the knowledge and understanding of the components involved in hydronics and the \u201csequence of operation\u201d for our gas systems. That having been stated, let\u2019s turn our attention to the physical aspects of the wiring installation for our systems.\n

Wire Versus Cable<\/h1>\nThe terms \u201cconductor\u201d and \u201cwire\u201d are synonymous, meaning they are referred to as the same when describing the actual component that will carry current between two points in a circuit. Wire is made of either copper or aluminum, with copper being the material of choice. Solid wire is used in permanent installations that won\u2019t be subjected to much movement or vibration in their life. Stranded wire is used in extension cords for portable equipment where there will be much movement and portability in use. In either case, the wire insulation on each conductor keeps the wires from unwanted contact with each other or the equipment around it.\n\n[caption id=\"attachment_194\" align=\"aligncenter\" width=\"831\"]\"Figure Figure 1 Solid-wire non-metallic sheathed cable[\/caption]\n\n[caption id=\"attachment_194\" align=\"aligncenter\" width=\"680\"]\"\" Figure 2 Stranded-wire extension cord[\/caption]\n\nWhile extension cord can be allowable for limited use in situations where equipment must be moved often for cleaning or routine maintenance, it is not acceptable for use in permanent installations of fixed equipment.\n\nCables consist of individual insulated conductors, contained within a jacket or sheath. The wire insulation is normally either rubber or some variety of plastic. The sheath could be a vinyl material, such as in an NMD90 cable, as seen below, or could be more robust so as to protect the wire from damage, as in the armoured cable also shown below.\n\n[caption id=\"attachment_194\" align=\"aligncenter\" width=\"400\"]\"\" Figure 3 2-conductor non-metallic sheathed cable (NMD90)\u00a0[\/caption]\n\n[caption id=\"attachment_194\" align=\"aligncenter\" width=\"400\"]\"\" Figure 4 3-conductor armoured cable\u00a0[\/caption]\n\nSome of the metal sheath of armoured cable must be removed when making wire connections. To do so, first bend the\u00a0cable\u00a0until the\u00a0armour\u00a0begins to pop open. Next take a saw blade or side cutters and cut\u00a0through the remaining\u00a0armour\u00a0avoiding coming into contact with the conductors. Once the\u00a0armor\u00a0is\u00a0cut\u00a0through, remove the\u00a0armor\u00a0sheath to expose the conductors. A split plastic bushing should be pushed into the end of the metal sheath to protect the issuing conductors from abrasion.\n

Media Attributions<\/h3>\n