WEG Mobile substations, 50 MVA dual-voltage class
WEG mobile substations, dual-voltage trailer units built in Brazil and integrated by Zest WEG
This model is part of SecondWatt’s transformer research catalogue. Specifications and price observations are included where supported by sources. Equipment availability and commercial terms require confirmation.
WEG mobile substation dossier: 50 MVA dual-voltage trailer units from Brazil, Zest WEG integration, delivered-project specs, market watch, inspection.
WEG lists mobile substations as a current catalog category under Mobile Solutions within its substations portfolio. The mobile transformers are built by WEG in Brazil, and turnkey mobile substations are integrated by Zest WEG, its South African subsidiary. WEG has stated that it manufactured the first mobile substations built in Africa. WEG publishes the rating envelope inside its product catalog rather than on the public category page; the ratings below are those confirmed by delivered projects.
The largest documented unit is the Zest WEG 50 MVA mobile substation delivered to Electricite De Guinee and commissioned in early 2022, procured through Robustrade of Dubai. Its differentiator is dual voltage: the primary is rated 110 kV or 60 kV and the secondary 20 kV or 30 kV, on three trailers, with the dual-voltage mobile transformer built by WEG Brazil. Named applications are multi-point grid distribution, substation maintenance cover, and temporary power for mining and large projects. WEG has also delivered a mobile substation to CEA Equatorial in Amapa, Brazil.
No used WEG mobile substation was listed for sale in August 2026. A generic used-mobile channel does exist through Surplus Record's three-phase categories and through Delta Star's factory remanufacturing program, which is the structured second-life route for this class regardless of nameplate.
Why it matters
Dual-voltage design lets one mobile serve two different grid standards, which is a real advantage for utilities running mixed systems and rare in a class where most units are built for a single service voltage. With fixed power transformers quoting up to four years at high capacity, mobiles are the standard bridge asset, and WEG's growing US footprint makes Brazil-built mobiles a supply line worth tracking.
Who buys it
Utilities in Latin America and Africa are the documented buyers, using mobiles for outage cover and rural multi-point service; miners take temporary power. US data center buyers would encounter WEG mobiles only through import, competing against domestic Delta Star and Hitachi Energy fleets with established service networks.
Role in the data center
Not yet a US data center asset. Its relevance is as future rental-pool supply as WEG's US presence grows, and as the dual-voltage design benchmark for campuses abroad that sit on mixed-standard networks, where a single mobile has to serve two service voltages rather than one.
Key specifications
| Largest documented rating | 50 MVA |
|---|---|
| Primary voltages | 110 / 60 (dual-rated) kV |
| Secondary voltages | 20 / 30 kV |
| Trailer count (50 MVA unit) | 3 |
| Manufacture / integration | WEG Brazil / Zest WEG |
| Reference commissioning | early 2022 (Guinea) |
| Brazil utility delivery | CEA Equatorial, Amapa |
| Africa production first | first mobile substations made in Africa |
| Named applications | grid distribution, substation maintenance cover, temporary power for mining and large projects |
| Catalog category | Mobile Solutions, within Substations |
| Procurement route, Guinea unit | Robustrade, Dubai |
| Customer, Guinea unit | Electricite De Guinee |
| Class transport standard | IEEE C57.150-2023, units of 10 MVA and above |
Technical summary
Catalog status: current WEG category, Mobile Solutions within Substations. Largest documented unit: 50 MVA. Primary: dual-rated 110 kV or 60 kV. Secondary: dual-rated 20 kV or 30 kV. Configuration: three trailers with a dual-voltage mobile transformer. Manufacture: WEG Brazil; turnkey integration by Zest WEG, South Africa. Reference customer: Electricite De Guinee, commissioned early 2022, procured through Robustrade of Dubai. Second reference: CEA Equatorial, Amapa, Brazil. Named applications: multi-point grid distribution, substation maintenance cover, temporary power for mining and large projects. Transport standard for the class: IEEE C57.150-2023 for units of 10 MVA and above, applied at each relocation.
Major variations
Two build types appear in WEG's delivered work: transformer-only mobiles and full mobile substations carrying switchgear and protection alongside the transformer. Dual-voltage design is the documented differentiator on the largest unit, with the primary rated for two service voltages and the secondary for two distribution voltages on a single trailer set, which suits utilities running mixed-standard networks. WEG has also announced a digital mobile substation for the Brazilian market; the announcement gives the product name without a published rating envelope.
Configurations and options
Units are engineered per project, and the largest documented example sets the reference: a 50 MVA mobile substation on three trailers with a dual-rated 110 kV or 60 kV primary and a 20 kV or 30 kV secondary, delivered to Electricite De Guinee and commissioned in early 2022 through Robustrade of Dubai. Build type is the first choice, a transformer-only mobile or a full mobile substation carrying switchgear and protection alongside the transformer. Manufacturing splits accordingly: WEG builds the mobile transformers in Brazil and Zest WEG integrates the turnkey substations in South Africa. WEG has announced a digital mobile substation for the Brazilian market with the product name confirmed but no published rating envelope, and the catalog rating envelope, BIL and IEC 61850 options sit inside the WEG product catalog rather than on the public category page as of August 2026.
Compatibility and dependencies
The dual-voltage design is the distinguishing dependency: the primary is rated for two service voltages and the secondary for two distribution voltages on one trailer set, so a single unit covers a mixed-standard network where a fixed transformer would need two. Beyond that it has to land on an existing yard: high-voltage and low-voltage terminations to the source and the distribution, a protection and control scheme the operator will accept, a grounding-grid connection, level ground, and station service for cooling and controls. Impedance still has to be matched to the interrupting duty of the breakers it feeds and BIL to the arrester scheme. Because a mobile is permanently transport-exposed, IEEE C57.150-2023 applies at 10 MVA and above at every relocation, so impact recording and post-move inspection recur rather than happening once.
Pricing and availability
Trend: rising No mobile substation price history is published, so what follows describes the fixed transformers a mobile stands in for. Electrical Trader's price history, published 2026-04-01, puts power transformer prices up 77% between 2019 and 2026 and generator step-up units up 45% since 2019, on copper up roughly 70% and grain-oriented electrical steel up 80-100% from 2020 to 2025. Terrapin Construction Group had substation units at 65-110 weeks and GSUs at 100-150+ weeks on 2026-06-10, and PwC via pv magazine USA on 2026-05-11 put high-capacity units at up to four years. That queue is what creates demand for mobile capacity. Lead time, new: Engineered to order; quoted per project. Lead time, used or refurbished: 2-12 weeks. Warranty, used: 3-year typical from major US rebuilders.
Lifecycle and maintenance
Liquid-filled transformers routinely serve 30-40 years with annual oil screening, DGA on a 1-2 year cadence (or continuous online monitoring on critical units), and gasket or bushing service as tests dictate. Major US rebuilders remanufacture units to like-new condition with warranties up to 3 years (T&R Electric, Sunbelt Solomon), and reconditioned stock ships in days against 65-210 week new-build queues. Remaining paper life, estimated by furan testing, governs end-of-life valuation.
Thermal and emissions profile
Transformers produce no combustion emissions; the regulatory profile is efficiency and fluid. US distribution-class units fall under DOE 10 CFR 431 Subpart K efficiency standards, amended in 2024 with compliance from 2029 requiring 10-30% lower losses than 2016 levels. Fluid choice drives fire and environmental posture: mineral oil versus FR3 natural ester with a 360 C fire point and ready biodegradability. Legacy units require PCB screening, with clean units documented below 2 ppm.
Common failure points
- Windings — Dielectric failure; windings dominate major-failure statistics in CIGRE TB 642
- Bushings — Failure share rises with voltage class; OIP bushing faults can rupture tanks
- OLTC — Contact and mechanism wear; prominent failure source on substation units
- Winding deformation — Through-fault or transport damage shifting SFRA signature
- Cooling system — Pump, fan, and radiator degradation derating the unit
- Moisture and paper aging — Furans in oil and reduced degree of polymerization
Inspection checklist
DGA: dissolved gas analysis per IEEE C57.104; combustible-gas trend rise between 2 samples triggers investigation. Oil quality: dielectric breakdown, moisture, acidity, and furan tests; degree of polymerization below 200 marks end of paper life. Insulation resistance: megger HV/LV/ground; polarization index of 2.0 or higher passes. Power factor: insulation power factor testing; values above 1.0% on oil-filled windings warrant investigation. Turns ratio: TTR on all taps; deviation beyond 0.5% from nameplate fails. Winding resistance: three-phase balance within 2% between phases. Bushings: capacitance and power factor test; bushing failure share rises with voltage class per CIGRE TB 642. OLTC: inspect on-load tap changer diverter and selector; OLTCs are a leading failure component in CIGRE TB 642 fleet surveys.
Procurement channels
The WEG catalog channel and Zest WEG for new and turnkey units, quoted per project. No used WEG mobile substation was listed for sale in August 2026, and no WEG mobile pricing is published. Buyers pricing the class work through generic used-mobile channels instead: Surplus Record's three-phase categories and Delta Star's factory remanufacturing program, which is the only structured second-life route in this class.
Regional notes
The transformers are built in Brazil and the turnkey substations integrated in South Africa by Zest WEG, and WEG states it manufactured the first mobile substations built in Africa; documented deliveries are to Guinea and to Brazil. The largest documented unit's 110 kV or 60 kV primary and 20 kV or 30 kV secondary are IEC-market voltages, not the 69 or 138 kV primaries and 12.47 or 34.5 kV secondaries a North American utility specifies, so a US buyer is looking at a different build rather than the same unit. Frequency is set at manufacture. Brazil-origin equipment carries Section 232 50% tariff exposure on non-US steel and aluminum content from 2025-08-18.