Busbar Conjunction (Joint) Box Series
Insulated boxes and covers for busbar joints and taps. Busbar joint boxes enclose and insulate the tap or joint so crews and adjacent metal are protected. We build them in insulating sheet to the busbar layout. Boxes are supplied with the covers and fixings for the joint arrangement you specify. Yes. Send the busbar layout and we build the box, cover and fixings to fit.
Technical specifications
| Material | Insulating laminate |
| Use | Busbar joint / tap enclosure |
| Supply | Box + cover + fixings |
| Standard | ASTM or IEC standards referenced in your drawing; COA supplied per batch. |
| Operating temperature | Per drawing specification |
| Dielectric strength | ≥ 20 kV/mm (per ASTM test method) |
💾 Datasheets & Test Reports
Download the technical data sheet for this product (PDF).
Applications by industry
- Distribution conjunction (junction) boxes for load-taking busbars
- Motor control center busbar transition boxes
- Transformer secondary bus riser junction boxes
- Splitter/feeder junction boxes in panel rooms
- Busbar tap and joint isolation boxes
- Prefabricated busway coupling boxes
Why insulating laminate + shrink assembly for this application
The junction box confines the joint, creepage and phase separation of take-off busbars into a compact insulated envelope, so live metal stays inside a cTc-compliant barrier.
Confirm ingress rating and phase separation against the box class; vents and cable entries must be designed for the take-off exits, not left to field drilling.
Standards: IEC 60439 / IEC 61439 (LV switchgear assemblies), UL 508A (USA).
Feature and remaining-wall review
CNC turning, grinding, drilling and milling to your drawing. Tolerances and gaging methods agreed before quotation. Review feature depth, edge distance and remaining wall on Busbar Conjunction (Joint) Box Series against the critical geometries. Capability is confirmed on your drawing, not from a blanket tolerance.
Inspection and traceability
We state the control plan with you. Batch traceability links raw material lot to finished part.
- First-article inspection (FAI) per your plan
- In-process dimensional checks at every station
- Batch certificate of conformance (COA) supplied on request
- Lot traceability to incoming material certificate
- Dielectric strength and insulation resistance testing available on request
Related components
Heat-Shrink Busbar Sleeve
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800V Busbar Heat-Shrink Tubing
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GPO-3 Polyester Glass Sheet
Related insulation component from the WELLELE catalog.
Common questions
Where would you specify Busbar Conjunction (Joint) Box Series?
Typical applications are busbar joint / tap enclosure. Give us the duty plus the environment, and we will either confirm this grade for Busbar Conjunction (Joint) Box Series or point you at the one that fits.
Which material is Busbar Conjunction (Joint) Box Series manufactured from?
The material is Insulating laminate. Alternate grades can be quoted against your drawing.
Is a material certificate of analysis provided for Busbar Conjunction (Joint) Box Series?
A material certificate of analysis goes out with each batch of Busbar Conjunction (Joint) Box Series. Add first-article inspection or dielectric strength testing if your quality plan requires the report.
Can Busbar Conjunction (Joint) Box Series be produced to a customer drawing?
Dimensions are supplied to your drawing. Send the print with the quantity you need and we will quote to it.
Engineering Guides & Selection Notes
Related reading on the selection and specification decisions behind Busbar Conjunction (Joint) Box Series.
Get pricing for Busbar Conjunction (Joint) Box Series
Send the drawing for Busbar Conjunction (Joint) Box Series and state the annual volume. We check the grade against duty and tolerance, verify the bore, outside diameter, wall and any features of Busbar Conjunction (Joint) Box Series, and reply with manufacturability notes and pricing.