Eaton Power Xpert UX primary switchgear (IEC, to 36 kV via UX 36)
Manufacturer: Eaton
Eaton Power Xpert UX, the SF6-free IEC primary flagship to 4,000 A and 50 kA with a 36 kV variant
This model is part of SecondWatt’s switchgear research catalogue. Specifications and price observations are included where supported by sources. Equipment availability and commercial terms require confirmation.
Eaton Power Xpert UX dossier: SF6-free IEC primary switchgear to 4,000 A and 50 kA with AFLR arc class and a 36 kV variant, market structure, inspection.
Power Xpert UX is Eaton's flagship IEC primary MV switchgear: air and cast-resin insulation with vacuum interrupters, SF6-free throughout, in single and double-busbar (duplex) builds sold through EMEA, APAC, and Middle East catalogs. Voltage classes run 3.6/7.2/12/17.5/24 kV at 630-4,000 A (2,500 A maximum at 24 kV), breaking capacity to 50 kA/3 s, and internal arc classification AFLR up to 50 kA/1 s (31.5 kA/1 s at 24 kV), with LSC2B service continuity and PM partition class under IEC 62271-200. The UX 36 variant extends the platform to 36 kV, 2,500 A, 31.5 kA/3 s.
Eaton publishes BIL values in brochure BR022008EN rather than on the product pages.
UX is the IEC benchmark Eaton brings to fights against UniGear ZS1, NXAIR, and PIX, and its 50 kA AFLR arc rating at SF6-free construction is the differentiating spec.
Why it matters
UX pairs the category's toughest arc rating tier (AFLR 50 kA/1 s) with SF6-free construction, the combination EU utilities now specify by default. Its zero-surplus structure is typical of IEC primary lineups, which do not reach a used market until decommission waves begin.
Who buys it
IEC-market utilities, heavy industry, and infrastructure projects specify UX for primary substations; UX 36 serves 33-36 kV networks.
Role in the data center
Primary medium-voltage distribution for IEC-market campuses and inside imported package plants and process skids, taking the incoming feed into transformer and feeder bays. The SF6-free construction with an AFLR 50 kA arc rating is the combination that suits dense urban interconnects where fault levels are high and a gas inventory is unwanted.
Key specifications
| Voltage classes | 3.6-24 kV (UX); 36 kV (UX 36) |
|---|---|
| Current range | 630-4,000 A |
| Breaking capacity | to 50 kA / 3 s |
| Internal arc | AFLR to 50 kA / 1 s |
| Service continuity | LSC2B / PM |
| UX 36 ratings | 36 kV / 2,500 A / 31.5 kA 3 s |
| Builds | single and double busbar (duplex) |
| Insulation | air + cast resin + vacuum (SF6-free) |
| Breaking capacity at 24 kV | 20-31.5 kA / 3 s |
| Internal arc at 24 kV | AFLR 31.5 kA / 1 s |
Technical summary
Voltage classes: 3.6 / 7.2 / 12 / 17.5 / 24 kV; UX 36 at 36 kV. Current: 630-4,000 A (2,500 A max at 24 kV). Breaking: to 50 kA / 3 s. Peak withstand: 63-130 kA by class. Internal arc: AFLR to 50 kA / 1 s (31.5 kA at 24 kV). Service continuity: LSC2B; partition class PM. Insulation: air + cast resin; vacuum interrupters; SF6-free. UX 36: 36 kV / 2,500 A / 31.5 kA 3 s. Builds: single and double busbar (duplex). Standard: IEC 62271-200.
Major variations
UX ships in single-bus and double-busbar duplex builds, plus the UX 36 variant at the 36 kV class rated 2,500 A and 31.5 kA/3 s. Panels cover incomer, feeder, bus-riser and metering duties. The electrical envelope narrows with voltage: up to 50 kA/3 s and AFLR 50 kA/1 s through 17.5 kV, but 20-31.5 kA/3 s and AFLR 31.5 kA/1 s at 24 kV, with current capped at 2,500 A there against 4,000 A lower down. BIL tables live in brochure BR022008EN, and Eaton publishes 12 kV case studies separately.
Configurations and options
Order variables are the busbar arrangement, single or double-bus duplex; panel duty, incomer, feeder, bus-riser or metering; and the electrical envelope, which narrows sharply with voltage. Through 17.5 kV the platform reaches 4,000 A with breaking capacity to 50 kA/3 s and internal arc classification AFLR 50 kA/1 s; at 24 kV it is capped at 2,500 A with 20-31.5 kA/3 s and AFLR 31.5 kA/1 s. UX 36 is a separate variant at 36 kV, 2,500 A and 31.5 kA/3 s. Service continuity class LSC2B and partition class PM are stated for the platform. BIL values by class are published in brochure BR022008EN rather than on the product pages.
Compatibility and dependencies
Insulation is air plus cast resin with vacuum interrupters and no SF6 anywhere in the design, which removes gas handling from installation, extension and decommissioning but does not change the clearances the arc classification was tested with. LSC2B service continuity and PM partition class define what can be worked on with the rest of the lineup live, and that is the specification a maintenance philosophy has to be written against. Bus rating and breaking capacity must be matched to the upstream transformer and network contribution at the specific voltage, since the 50 kA figure does not survive to 24 kV. A US-landed lineup inside a package plant needs the Eaton spares route established at acquisition, because domestic dealers rarely stock IEC breaker frames.
Pricing and availability
Trend: rising Lead time, new: 52-104 weeks (IEC MV class by voltage). Lead time, used or refurbished: No secondary channel exists. Warranty, used: 1-year typical from reconditioning dealers.
Lifecycle and maintenance
Metal-clad MV switchgear routinely serves 40+ years: vacuum interrupters rated for 10,000-30,000 operations far outlast the mechanical duty standby service imposes, so lineup life is governed by insulation condition and relay/controls vintage. Breakers recondition readily and trade as units, while lineups modernize in place with digital relays and retrofit breakers. ANSI/NETA MTS acceptance testing at purchase plus PD surveys in service are the condition gates.
Thermal and emissions profile
Switchgear produces no combustion emissions, and SF6-free designs remove the category's one regulatory exposure: instead of SF6 (GWP 24,300), these units insulate with clean air, dry air, or pure air at GWP below 1 and interrupt in vacuum. That satisfies EU F-gas Regulation 2024/573, which bars new SF6 MV switchgear from the EU market from 2026, and California's CARB phase-out of new SF6 equipment acquisitions from 2025. Buyers avoid gas handling, leak reporting, and end-of-life recovery costs entirely.
Common failure points
- Vacuum interrupters — Loss of vacuum ends interrupting capability with no external sign
- Insulation tracking and PD — Partial discharge across dusty or damp insulation progressing to flashover
- Racking and interlocks — Damaged racking screws and defeated interlocks from forced operation
- Protection relays — Obsolete or drifted relays mis-operate under fault
- Instrument transformers — CT/VT failures disable metering and protection inputs
- Space heater failure — Condensation-driven tracking in unheated outdoor or humid gear
Inspection checklist
Vacuum integrity: hipot test each interrupter per OEM procedure (e.g., 36 kV test on 15 kV class). Insulation resistance: megger bus and breakers at 2,500-5,000 V; compare to ANSI/NETA MTS tables. Contact resistance: micro-ohm each pole; investigate imbalance beyond 50% between phases. Partial discharge: ultrasonic and TEV survey; investigate any reading 6 dB above baseline. Contact erosion: measure vacuum interrupter erosion marks against the OEM wear allowance. Racking mechanism: cycle connect/test/disconnect positions 3 times each; verify interlocks and shutters. Mechanism timing: verify open/close times; closing beyond 5 cycles flags mechanism trouble. Bus insulation: inspect epoxy and boots for tracking or corona; clean and torque joints. Instrument transformers: verify CT/VT ratios, insulation, and fusing.
Procurement channels
Eaton EMEA and APAC channels supply UX and UX 36 on project and framework orders. No surplus listing exists on any public platform as of August 2026, and none is expected until fleet turnover begins. Buyers acquiring a US-landed package plant containing UX panels should establish the Eaton spares route at acquisition rather than assuming a domestic dealer can supply IEC breaker frames.
Regional notes
An IEC 62271-200 product sold through Eaton's EMEA, APAC and Middle East channels, with no ANSI listing and no North American catalogue presence; UX and UX 36 reach US sites inside imported package plants and process skids rather than as specified campus gear. A 50 Hz lineup is not usable on a North American 60 Hz project without significant engineering, and IEC breaker frames and spares have to come through Eaton's international channel rather than a domestic dealer shelf.