Frequently Asked Questions Answered by American Fittings

Frequently Asked Questions Answered by American Fittings

Raceway systems such as EMT and rigid conduit are permitted by most codes to be embedded in concrete. The solid exterior of these conduits eliminates the possibility of concrete entrance; however, the termination with the connector or coupling can be susceptible to concrete entering the raceway.

Want more information on non-metallic fittings manufacturers? Feel free to contact us.

The UL 514B testing procedure requires connectors or couplings to be assembled to the conduit inside a special concrete form. Then, Portland-type concrete is poured into the form and over the test samples. The concrete slurry is vibrated to remove any trapped air and allowed to cure. After curing, the fittings are chipped out of the concrete and examined for concrete penetration.

Although compression style connectors and couplings generally pass these tests in all trade sizes due to their gland ring design, set screw types may struggle to conform to UL or CSA concrete penetration requirements. When the set screw is tightened onto the conduit, the fitting and/or conduit material will ‘yield’ or stretch enough to create an opening at the conduit/fitting connection.

Set screw fittings in smaller trade sizes (1/2", 3/4", and 1") are less likely to stretch to the point of allowing concrete to enter. However, fittings 1-1/4" and larger will yield enough to let concrete penetrate the raceway. UL and CSA allow for product carton markings that specify “Concrete-Tight When Taped” on fittings that fail testing, as tape prevents concrete from entering the raceway. The taped joint must completely encircle the conduit/fitting connection. We recommend using duct tape or a similar durable type of tape.

Electrical Conduit Fittings Buying Guide

Even the most experienced electricians and project managers need tips every now and again. We get questions all the time at our counters and via email about what types of conduit fittings will work in various situations. 

Buying the right electrical conduit fittings for your project is as important as getting the right conduit itself. Fittings don’t only connect lengths of conduit but also connect conduits to walls, boxes, and other enclosures. Depending on the conduit you plan to use, the choice of fitting can determine the success of the installation.

Not Sure Where to Start? Start with the Application

The first step (and this is likely already a part of your project plan or permit pack) is to define the application for the conduit.

What regulatory aspects need to be met in order for your project to pass inspection and satisfy national and local safety regulations? Not only does the material need to meet NEC standards, but it also should be safe for the building itself.

If you want to learn more, please visit our websiteflexible metal conduit water proof manufacturers. Conduit fittings are available in various materials, including die-cast zinc, nickel-plated brass, nylon, and galvanized steel. The NEC’s standards don’t always specify which material you should use, but before finalizing your budget (and your first order), consider whether the material needs to be:

• Watertight or waterproof
• Corrosion-resistant or resistant to harsh chemicals for petro/industrial/food applications
• Utilized for HVAC and/or ventilation systems
• Impact-resistant for industrial applications or motorized equipment
• Explosionproof or for hazardous locations

Insulated fittings further ensure that internal wires don’t suffer damage due to friction or wear. If you’re unsure, contact an experienced dealer for answers about materials, quantities, and more. 

What Are the Common Types of Conduit Fittings?

This is not an exhaustive list, but the most common conduit types and their applications include:

• Metallic and nonmetallic couplers: Used to join lengths of non-flexible conduit.
• Connectors: Attach conduit to enclosures like electrical boxes. Many are designed to snap into an opening without a locknut for faster installation. Use metallic connectors for metal conduit and PVC connectors for PVC conduit. 
• Conduit bodies: Provide a service entrance to the interior of a raceway for inspection and maintenance. They can also be used to enable more bends in one section of conduit.
• Locknuts and insulating bushings: Used when attaching conduit to a box or enclosure.
• Reducing washers: Installed with a locknut to reduce the size of the knockout or opening to fit a smaller conduit.
• Straps/hangers: Secure wire and conduit to walls, ceilings, and prevent sagging or buckling.
• Nipples: Threaded lengths of conduit that make it easier to join pieces of equipment together.
• Elbow: Provides an angle or direction change in a conduit run. Available for both metallic and non-metallic conduit in either 22-, 30-, 45-, or 90-degree bends.
• Raintight hubs: Necessary for most outdoor applications, they have both internal and external threads to make connections that prevent moisture from seeping into the enclosure.

Most Popular Conduit Materials

Here’s a quick list of the most popular conduit varieties that should satisfy most electrical applications:

• Electrical metallic (EMT)
• Galvanized rigid (GRC)
• Intermediate metal (IMC)
• PVC
• Liquid-tight non-metallic (NMLT)
• Liquid-tight metallic (UA)

Most conduit is available in custom lengths and can be bent to spec on-site by a professional. Have questions about conduit cutting and bending equipment? Let us know and we’ll connect you with an expert.

As Always: Stay Safe!

Since we are talking about electrical components and equipment, here’s a quick reminder that HOLT takes everyone’s safety very seriously. We deal mostly with trade professionals, but it bears repeating that failing to follow the right precautions when working with electrical components can cause injury or death.

Always follow the manufacturer’s instructions and wear all appropriate safety gear (a HOLT expert can tell you what you need). If you’re trying DIY projects, always verify what permits your municipality requires, and follow all codes for both commercial and residential safety.

HOLT is Your Electrical Supply Partner

We don’t build. That’s your job. We ensure that we have everything the electrical tradesperson needs to get the job done. The team at HOLT is always figuring out new ways to make your work go smoothly, especially concerning your budgets and timelines. Whether you need a site pod, last-minute delivery, or some friendly advice, contact us today and let us know what you need.

Are you interested in learning more about rotating type conduit fitting? Contact us today to secure an expert consultation!