Thomas & Betts 4 Inch Insulated Grounding Bushing with 14-4 AWG Range
Professional Electrical Grounding Solution with Malleable Iron Construction
The Thomas & Betts 4 inch insulated grounding bushing delivers reliable electrical grounding performance with malleable iron construction for durability and long-term service. Designed to accommodate 14-4 AWG wire range, this professional grounding bushing provides secure electrical connections in commercial and industrial applications where dependable grounding is essential.
Professional Features & Benefits
- 4 Inch Size: Accommodates larger conduit installations for versatile application compatibility
- 14-4 AWG Wire Range: Supports multiple wire gauges for flexible installation requirements
- Malleable Iron Construction: Provides superior durability and corrosion resistance for long-term reliability
- Insulated Design: Ensures proper electrical isolation while maintaining effective grounding performance
- Professional Grade: Engineered for commercial and industrial electrical system requirements
- Thomas & Betts Quality: Backed by proven manufacturing standards for consistent performance
Technical Specifications
- Department: Electrical
- Material: Malleable Iron
- Number Of Batteries: 0
- Product Group: Miscellaneous
- Product Subgroup: Brushes
- Product Type: Grounding Bushings & Accessories
Professional Applications
- Commercial Electrical Installations
- Industrial Facility Grounding Systems
- Multi-Unit Residential Properties
- Professional Office Buildings
- Retail and Service Establishments
- Light Industrial Applications
- Emergency Service Facilities
Why Choose Thomas & Betts Quality?
Thomas & Betts grounding bushings deliver proven reliability through malleable iron construction and precision engineering. The professional-grade design ensures consistent grounding performance in demanding electrical applications, providing the durability and dependability that electrical professionals trust for critical installations.
Manufacturer Resources
Product Specs
- Product Subgroup:
- Grounding & Bonding
- Product Type:
- Grounding Bushing
- Product Group:
- Grounding & Bonding
- Department:
- Electrical
- Product Material:
- Malleable Iron
- Number Of Batteries:
- 0
Thomas & Betts 3872 – Frequently Asked Questions
1) What conduit sizes do the Thomas & Betts insulated grounding bushings come in?
Three trade sizes: 1 inch (part 3872), 2 inch (3875), and 4 inch (3879). Order by the trade size of the rigid conduit or IMC the bushing threads onto, not by the wire size.
2) What size grounding conductor will the lay-in lug on these T&B bushings accept?
The lug takes 14 AWG through 4 AWG copper. If your equipment grounding conductor is larger than 4 AWG, as it often is on a 4 inch feeder run, this lug will not land it and you need a bushing with a bigger conductor range.
3) Why use an insulated grounding bushing instead of a plain locknut and bonding jumper?
Two jobs in one fitting: the insulated throat protects conductor insulation where wire leaves the conduit end, and the integral lug gives you a bonding point to run a jumper to the enclosure ground bar. On a concentric or eccentric knockout, or where the raceway is not reliably bonded to the box, that lug is how you establish the bonding path. A plain insulated bushing gives you throat protection only, with nowhere to land a grounding conductor.
4) Is the body metal or plastic, and will it hold up in a damp industrial room?
The bushing body is malleable iron, so it is a metallic fitting with a plastic or phenolic insulating throat liner. Malleable iron takes mechanical abuse better than die cast on large conduit ends and is the usual choice for industrial and commercial raceway. Note it is a metal fitting, so the throat insert is the only thing isolating the conductor.
5) Does the grounding bushing thread onto the conduit or into the box?
It threads onto the male threaded end of the conduit, inside the enclosure, replacing the inner locknut position. You still need the outer locknut on rigid or IMC, and you run a bonding jumper from the bushing lug to the ground bar or enclosure bonding screw.
6) Do I need one grounding bushing per conduit or just one per panel?
One per raceway that needs bonding. Each conduit entering the enclosure gets its own bushing and its own jumper to the ground bar, so count your conduit entries and match trade sizes: 1 inch uses part 3872, 2 inch uses 3875, 4 inch uses 3879. Mixed sizes on one panel means ordering more than one part number.
7) Is the bonding jumper wire included with the T&B 3872 grounding bushing?
No. You get the bushing with its lay-in lug; the grounding conductor is supplied separately and must fall in the 14 through 4 AWG range the lug accepts. Budget for the jumper wire and any ground bar lug at the enclosure end.
How fast can I get the Thomas & Betts 3872 delivered?
Most orders ship the same day from our distribution partners, with quick delivery throughout the
continental
U.S.
Need it urgently? Contact Us for expedited shipping options.
Can I return it if it doesn’t work for me?
Yes—ZenSupply offers a hassle-free return policy. If the product isn’t the right fit,
reach out to our support team for a return authorization or setup a return by following our return instructions.
Does the Thomas & Betts 3872 come with a warranty?
Absolutely. The Thomas & Betts 3872 is backed by a manufacturer’s warranty.
For full warranty terms, check the product documentation or Contact Us.
How do I get technical support or installation help for the Thomas & Betts 3872?
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