The United States Electrical Contracting and Installation industry is a $170 billion a year behemoth made up of over 75,000 businesses that together serve virtually all sectors of the national economy. Within this industry, we find a wide variety of manufacturers, vendors, distributors, wholesalers, contractors, fabricators, and service technician companies, all working together to deliver electrical solutions for an even larger number of end users. The electrical hardware that these groups rely upon is the topic of this second article in our Application series, coming up below!
In the electrical world, safety is paramount. We often don’t recognize just how safe, reliable, and resilient the electrical infrastructure that surrounds us is – a testament to the regulatory codes that demand stringent compliance with extensive design and testing requirements. The National Electrical Code (NEC) and National Fire Protection Association (NFPA) govern the design, installation, and operation of electrical devices large and small, while also requiring very robust testing qualifications before devices may be sold. Testing typically is run through an independent testing agency such as the Underwriter’s Laboratory (UL), resulting in devices being ‘UL Listed’ or ‘UL Certified’ for safe use.
Just as with most other trades, electrical installation work relies on a combination of highly specialized and commodity hardware selections to complete a given project. Usually, hardware that directly conducts electrical current falls into the specialized category, whereas general installation components are of the common variety. For the purposes of this article, we’ll focus on the common installation hardware, and leave the specialized, conductivity, and safety categories of hardware for a future discussion.
Do you have an Electrical application but are unsure of which fastener meets your project’s requirements? E&T Fasteners offers expert support and product selection between the above options and more! Contact us to discuss your application, or to see our entire fastener catalog, visit our product selection here.
Electrical Hardware Application Types
Electrical hardware can be separated into distinct application categories, each describing a particular use case. We’ll outline the most common hardware application groups below.
|Application Category||Common Hardware Components|
| Fig. 1 – Electrical Suspended Strut Supports ||Indoor installation of electrical conduit typically utilizes suspended strut trapeze hangers, anchored into each room’s ceiling. Strut trapezes or racks allow for multiple conduits to be installed without having to hang each circuit independently. Multi-layer trapezes, and multiple adjacent trapezes provide ways to distribute weight and provide routing flexibility for large numbers of conduits. Wall hangers are just as common for vertical drops, anchoring strut directly to walls. Common hardware includes: |
Threaded rod, couplings, stiffeners, sleeves
Unistrut and formed-channel hangers, channel nuts, channel washers
Strut clamps, straps, and brackets Seismic supports
Concrete ceiling and wall anchors
| Fig. 2 – Rough Electrical Hardware ||Rough electrical installation refers to work that will be covered up, buried, or otherwise hidden from view once complete. Most commonly, this refers to electrical circuits ran free-air or in EMT conduit installed within walls, ceilings, and under slabs. Hardware for rough installation provides support, anchoring, routing, and separation for circuits and fixtures. Because rough installation work ends up behind cover, material options are typically lighter duty and single-use, since they won’t be exposed to the elements. Examples are:|
Cable clips, straps and clamps,
cable staples, tie-off anchors,
screws and lag bolts, wire ties and straps,
looms and sleeves, separators,
grommets, and bulkhead fittings.
| Fig. 3 – Cable Tray and Gutter Supports ||Combining the concepts of trapeze racks and free-air rough electrical, an electrical installation method using cable trays and gutters provides a cost-effective solution for clean, dry, indoor environments. Cable trays are long wire baskets supported on strut racks, in which free-air, heavily insulated cables, and wires are ran. These wire bundles are visible after installation and not covered up. This method reduces installation cost versus using conduit, but is only suitable where cabling is safe from the elements and general wear. Electrical gutter is similar to tray but has solid sides and a cover, such that wire is bundled together inside but is not visible from the outside. |
Strut hardware examples are:
Metal brackets and connector plates,
Machine screws, nuts, bolts, and washers,
Grounding nuts and bolts,
Seismic supports and hardware cable, wire, and cable sets.
| Fig. 4 – Control Panel Hardware ||Electrical distribution and control components are often installed into protective control enclosures (or panels). Fabricating these control panels combines electrical wiring and metal assembly hardware types. Attaching wireways, DIN rail, and other large components to the sub-plane calls for sheet metal hardware, whereas electrical circuit terminations call for more specialized electrical hardware. |
Self-tapping, self-drilling screws
“Tek” and “Zip” screwsFine thread machine screws, nuts, washers
Tamper-proof screws Insulated screws, bolts, studs, and bosses
Wire ties, tie clips, straps, and adhesive pads
Bronze / brass grounding screws, nuts, and washers
Nylon lock nuts and lock washers
| Fig. 5 – Assorted Hardware ||As with most construction trades, electrical work taps into the wider general hardware pool in order to round out any given project. Since every project is different, installers and equipment builders alike will at some point pull from all sorts of commodity components to meet their needs. |
Standard hex, round, pan, and flange head bolts, washers, and nuts,
Quick-connect hardware such as wing nuts, pins, clips, and clamps,
Structural hardware such as carriage bolts, rivets, and anchors
Hex, Allen, and lobe-head hardware.
Materials and Features
Take for example two very dissimilar electrical installation environments: an electrical distribution substation located in a remote mountain pass, and a small ceiling light installed in your home’s hallway closet. In both cases, we find hardware that has to reliably perform in all of the environmental conditions that it will experience, but we can certainly imagine that your hall closet will see much less severe exposure than high-elevation mountains. Here is where materials, finishes, and all other specifications for hardware come into play – we must specify our hardware to be compatible with the conditions they will face, for the lifespan that they are expected to last.
Most Electrical applications have differing attributes that influence our hardware selections, depending on which part of the system and building space we’re working in. Let’s break down these attributes into fastener grades:
- Indoor components are often dry, clean, and at normal temperatures, calling for general grade hardware
- Outdoor components are often fully exposed to the elements, including all-day sun exposure being on top of building roofs, calling for weather-rated hardware
- Components installed within Electrical equipment are often exposed to harsher conditions, with high or low temperature, humidity, vibration, and general stress, calling for high-grade hardware
- Certain critical equipment areas will require even higher-performance components, such as within electrical distribution panels, main switchgear, large manufacturing equipment, and IT networking gear, calling for specialty engineering hardware
Using the above grades, buyers should consider the following material and feature specifications as a starting point, and then should discuss their application with a trained distributor to finalize their selection.
- General Grade Hardware – aluminum, brass, zinc-plated steel or bronze material with no applied finish; with standard threads
- Weather-Rated Hardware – steel with zinc, nickel, or galvanized plating; stainless steel type 18-8 or 304 with no applied finish; with standard or fine threads, and thread-lock compound
- High-Grade Hardware – high-strength steel with zinc or nickel plating; or stainless-steel type 316; heat treated; with fine threads, thread-lock compound, and high-temp coating if needed; structural grade / class if needed (imperial Grade 2 and 5 / metric Class 8 and 10 common)
- Specialty Engineering Hardware – stainless steel type 316, Hastelloy, forged steel, or other exotic materials; plated, coated, and / or annealed as needed; heat-treated; structural grade / class if needed (imperial Grade 8 / metric Class 12 common)
- Around electronics and electrical circuits, other special hardware requirements may call for non-conductive / non-metallic fasteners using bronze or plastic materials
Electrical buyers should also take special note of the conductivity potential of hardware in specific situations. For example, a non-conductive plastic or non-metallic material may be preferred, in order to reduce the risk of arc flash or other hazards. In other cases, bronze materials may be preferred so as to improve electrical conductivity over other materials and finishes, such as in grounding lug connections.
E&T Fasteners is here to help you navigate fastener and accessory options. Price quotes, availability, lead times, delivery confirmations, unique application suggestions – whatever your need, we’re here to take your call or email. For support and advice from our fully trained staff, speak with an E&T sales representative today.
About E&T Fasteners
With sales and support teams spanning the Continental US, E&T Fasteners is here to serve your hardware, fastening, and component needs both domestically and internationally. We are a stocking distributor of metallic, plastic, and exotic alloy fasteners, backed by our technical staff directly experienced in your unique applications. We can assist your specifying and selection efforts, providing engineered solutions, record-fast lead times, and stellar customer service from quote through delivery. Please let us know how we can help!