S Series Busbar Insulator — Willele
Stud-mount drum insulators for compact LV/MV panels, MCCs and DC bus assemblies.
Compression-molded BMC/SMC body with plated brass/steel inserts; stable tightening and insulation.
Two strength families: S525 (5 kV / 400 lbs) and S842 (8 kV / 700 lbs) with multiple heights and colors (orange, blue, green, white).
Introduction to S Series Busbar Insulators
Willele S Series busbar insulators combine a compact drum profile with a factory-installed stud, giving panel builders a fast, rigid mounting point for busbars while maintaining safe electrical isolation. The series is widely used in switchgear, MCCs, power-conversion cabinets and ESS/DC bus systems.
Each insulator is compression-molded from BMC/SMC and fitted with a plated metal insert, delivering repeatable tightening torque, dimensional stability under vibration/thermal cycling, and long-term service in low- to medium-voltage equipment.
Function and Purpose
Electrical insulation. The molded body forms a non-conductive barrier reducing phase-to-phase faults and arcing. Mechanical support. The threaded stud/insert provides a rigid anchor so busbars remain aligned during vibration and short-circuit forces.
Willele S Series Overview
Key Features
- Compression-molded BMC/SMC body for mechanical strength and dielectric stability
- Typical operating range: −40 °C to +140 °C (compound dependent)
- Plated brass or steel inserts/studs for high pull-out strength and corrosion resistance
- Compact drum geometry and stud-mount design speed up assembly
- Customization for color, insert type, thread, height and compound grade
Standard Color Options
Orange, Blue, Green, White (other colors on request).
Typical Applications
LV/MV switchgear, MCCs, rectifier & inverter cabinets, ESS/DC bus assemblies, transformer connections and industrial control panels.
Specifications
| MODEL | TENSILE STRENGTH (lbs) | VOLTAGE WITHSTAND (kV) | TORQUE (ft-lbs) | SCREW (mm) | COLOR OPTIONS |
|---|---|---|---|---|---|
| S525-1 | 400 | 5 | 6 | 5 | Orange, Blue, Green, White |
| S525-2 | 400 | 5 | 6 | 5 | Orange, Blue, Green, White |
| S525-3 | 400 | 5 | 6 | 5 | Orange, Blue, Green, White |
| S842-1 | 700 | 8 | 10 | 8 | Orange, Blue, Green, White |
| S842-2 | 700 | 8 | 10 | 8 | Orange, Blue, Green, White |
| S842-3 | 700 | 8 | 10 | 8 | Orange, Blue, Green, White |
Dimensions and Size Chart
Electrical and Mechanical Notes
Electrical
- Choose a family (S525 or S842) whose dielectric withstand exceeds your operating level and transients.
- Check creepage and clearance distances in the cabinet layout.
- Outdoor-grade compounds are available on request.
Mechanical
- Match thread size and depth to clamps and base plates; use the recommended tightening torque.
- Align bars so loads act axially on the stud; avoid prying forces on the shoulder.
- Re-check clamp tightness after the first thermal cycle when applicable.
Ordering Information
For a quick quotation and drawing, please provide: model (e.g., S842-2), thread size and insert material (brass/steel), quantity & destination, desired color, and any certification/inspection needs.
