Maintain overhead reliability with predictable fault protection.
Reliable transformer protection keeps your customers connected and crews focused on higher-value work. But as traditional fuses age and grid demands evolve, they can contribute to unexpected outages and maintenance.
For more predictable protection, deploy the VacuFuse II Self-Resetting Interrupter. This single-phase, resettable, transformer fuse-replacement device uses a vacuum interrupter to respond to faults.
Its reliable response helps reduce nuisance outages, eliminate fuse replacements, and keep your operations running smoothly.
Which VacuFuse II Interrupter Is Right for You?
The VacuFuse II interrupter is available in both fault-testing and non-fault-testing models.
Fault-Testing Model
Tests for permanent and temporary faults. Automatically restores power for temporary faults to avoid sustained outages. Locks and drops out for permanent faults.
Non-Fault-Testing Model
Provides fuse-like protection with a single operation per fault, while containing the arc. Drops out for faults. Ideal for applications where automatic reclosing isn’t desired.
How a Resettable Fault Interrupter Works
Watch how the VacuFuse II interrupter installs like a fuse but modernizes overhead transformer protection to avoid ongoing fuse replacements.
Why Utilities Choose the VacuFuse II Interrupter
Each model is designed to protect your transformer and minimize disruption to your overhead distribution system.
Interrupts faults without accumulating damage
Won’t cause sneakouts
Avoids nuisance outages and tripping
No fuse replacement, settings, or re-fusing errors to deal with
Coordinates easily
Supports flexible arrester placement
Simple installation and operation
Supports crew and environmental safety
Experience Even More Benefits with Fault Testing
Consider the VacuFuse II interrupter fault-testing model to keep temporary faults from causing sustained outages—and improve reliability in hard-to-reach areas.
EXPLORE FAULT-TESTING BENEFITSView the VacuFuse II Interrupter Construction and Design
Explore key components using the 3D product viewer below. For instructions, click the Help button.
Features that Deliver Smarter Protection and Improved Operations
Vacuum Interrupter
Sealed chamber opens quietly to extinguish arc without expulsion of debris.
Electronic Controls
Electronic controls avoid unexpected outages by not accumulating fuse damage.
TCC Curve Variety
Vast library of TCC curves makes coordination with upstream devices easy.
TCC Curve Shift Protection
Permanently accurate TCC curves are unaffected by overcurrent events.
Cutout Installation
Device installs into a cutout using standard utility tools and procedures.
Easily Resettable
Device is easy to reset after operation with no re-fusing required to prevent errors and reduce inventory.
Drop-Open Visible Gap
Device locks and drops out to indicate fault status, improving fault-finding.
Delayed Close
Automatic time-delay gives crews time to move away before the vacuum interrupter closes.
How Advanced Fault Protection Has Helped Utilities
See how VacuFuse technology contributed to improved storm resilience and restoration.
Integrated Solutions Lead to Greater System Resilience
Read Full Case StudyNeed Support?
S&C is here to help you through any stage in your grid-modernization journey, from system studies to operation videos. Explore more below.
Product Details
Information Bulletin 466-211 contains curve plots for all VacuFuse II Self-Resetting Interrupter TCCs. Data points for these curves can be found here.
(On mobile, swipe left for remaining ratings information.)
Table 1. Complete VacuFuse II Self-Resetting Interrupter—For a new installation. Includes VacuFuse II interrupter, cutout mounting (less mounting bracket), and connectors.
| Cutout Mounting Size, kV | Phase-to-Neutral Voltage Rating, kV | BIL, kV1 | Amperes | Amperes Interr., Sym. |
|---|---|---|---|---|
| Cont., RMS2 | ||||
| 15 | 7.2 - 9.0 | 110 | 20 | 6 300 |
| 25 | 7.2 - 9.0 | 150 | 20 | 6 300 |
- 1 BIL is achieved with the VacuFuse II interrupter dropped open.
- 2 Available in 2- to 20-ampere models, with minimum trip currents from 4 to 40 amperes.
Table 2. VacuFuse II Self-Resetting Interrupter Only—For retrofit in an existing present-production (“-R10” or “-R11”) S&C-only cutout mounting.
| Cutout Mounting Size, kV | Phase-to-Neutral Voltage Rating, kV | BIL, kV1 | Amperes | Amperes Interr., Sym. |
|---|---|---|---|---|
| Cont., RMS2 | ||||
| 15 | 7.2 - 9.0 | 110 | 20 | 6 300 |
| 25 | 7.2 - 9.0 | 125/150● | 20 | 6 300 |
- 1 BIL is achieved with the VacuFuse II interrupter dropped open.
- 2 Available in 2- to 20-ampere models, with minimum trip currents from 4 to 40 amperes.
- ● BIL is dependent on the cutout mounting into which the VacuFuse II interrupter is installed.