ALTERNATOR SUPPLY
At Central Group, our certified alternator specialists will assess your application requirements to recommend and supply the optimal alternator solution. Whether you’re operating in challenging industrial environments or standard conditions, we ensure reliable performance, and maximum uptime backed by our 50+ years of expertise and official partnership with Nidec Leroy-Somer alternators UK.
We can supply alternators from all leading manufacturers including Nidec Leroy-Somer, Stamford and Mecc Alte.
NIDEC LEROY-SOMER ALTERNATORS
LSA SERIES
Built for premium power generation, the LSA range delivers high efficiency, Class H insulation and robust design, making it suitable for marine, grid-connected and critical industrial systems.
TAL SERIES
Designed for telecom, commercial and industrial markets, the TAL range offers compact, cost-effective alternators with optimised electrical performance, ideal for prime and standby power applications.
INDUSTRIAL ALTERNATOR REPAIR, REWIND, OVERHAUL & SERVICING
At Central Group, we specialise in the repair, overhaul, rewind and preventative maintenance of industrial alternators and DC generators – supporting high-capacity power generation systems from 10kVA to 5MW+.
We pride ourselves on our complete alternator services. Undertaking all major repairs in our fully equipped workshop, in Knowsley, Merseyside, as well as conducting site services providing 24/7 support to customers across the length of the UK.
WORKSHOP SERVICES & REPAIRS
Our facility is purpose-built for heavy engineering including: featuring 20-tonne overhead crane capacity and the ability to dismantle even larger units for comprehensive repair.
- Large Frame Dismantling
- Full Overhauls
- Initial Inspection, Cleaning & Oven Drying
- Bearings – Replacement & Upgrades
- Stator & Rotor Rewinds – Visual Inspection & Resistance Measurement
- Machining of Parts
- Dipping Impregnation/VPI
- Vibration Measurements
- Investigations & Diagnostics
- Dynamic Balancing ISO G2.5
- 20-Tonne Lifting Capacity
- Finish – External Cleaning, Acceptance Testing & Repaint
INDUSTRIAL & COMMERCIAL APPLICATIONS
- Power Generation
- Telecommunications
- Data Centres
- Utilities
- Rental Power
- Manufacturing
- Critical Infrastructure
- Waste to Energy
- Universities
- Commercial Farms
- Marine
Alternator phases are determined by the number of coils in the stator. Three-phase-alternators produce more consistent power than single-phase alternators. Which one you need should be determined by the load or application.
Your alternators voltage determines
the types of devices or systems it can power.
Common voltage include:
480/277V, 440/254V,
220/127V, 208/120V
Single phase 240/120V 220/110V
Common voltage include:
346/600, 4100/2100, 13800/7620
Common voltage include:
3 phase 4160/2402V, 13800/7968V
NIDEC ALTERNATOR REPAIRS
UK KEY SERVICE PARTNER – NIDEC LEROY-SOMER ALTERNATORS
Central Group is the only UK Key Service Partner for Nidec Leroy-Somer alternators, making us the primary UK repair and service centre.
This partnership provides:
- Direct access to genuine OEM parts and spares
- Reduced lead times on critical components
- Manufacturer-aligned repair standards
- Technical support for both workshop and site-based repairs
- Rental Market Alternator repairs – fast turnarounds
For operators relying on Nidec Leroy-Somer alternators in standby, prime or critical power applications we guarantee reliable repairs, faster turnaround and long-term asset integrity.
ON-SITE ALTERNATOR SERVICES & POWER GENERATION SUPPORT
Our engineers provide UK-wide site services for industrial alternators and power generation equipment. Our services include preventative maintenance solutions, health checks and servicing of your assets as well as 24/7 emergency breakdown support.
- Re-fitting, Installing & Commissioning
- Emergency Breakdown Support
- On-site Bearing Replacement
- Laser Shaft Alignment
- Belt Alignment
- Preventative & Remedial Maintenance
- Vibration Analysis and Condition Monitoring
- On-site Testing
This allows us to support mission-critical standby and backup power systems, ensuring alternators are ready to perform the moment mains power fails.
FAST-TURNAROUND REPAIRS FOR THE RENTAL POWER MARKET
We understand the pressures of the generator rental market, where alternators must be returned to service quickly to avoid lost revenue.
Our repair processes are designed for speed without sacrificing quality, supporting rental fleets with:
- Rapid fault diagnosis
- Priority rewinds and repairs
- OEM component availability
Our focus is always on minimising downtime and maximising asset availability.
SERVICE DETAILS
INSPECTION LEVEL 1
- Offload at Central Group workshop
- Visual inspection and photograph, recording damaged or missing parts
- Removal of rotor
- Basic Static Tests (rotor and stator) with Megger & Digital Multimeter
- Remove bearing(s) and check for signs of wear and/or mechanical looseness
- Provide Inspection Level 1 report findings
STANDARD REPAIRS
- Supply and fit replacement bearing(s)
- Supply and fit replacement diodes
- Supply and fit replacement varistors
- Apply enveloping varnish
- Assemble unit
- Final testing of assembled unit
- Repair report
- Palletise unit ready for collection
INSPECTION LEVEL 2
- Items listed in Inspection Level 1 process
- Pressure wash, stove, stator and rotor windings
- Mechanical tolerance checks on housing, journals, keyways and couplings as required
- Baker surge test on rotor and stator windings
- Provide Inspection Level 2 report findings
OPTIONAL EXTRAS
(not included as standard)
- Remove alternator from canopy and refit on completion of work
- Store canopy / store canopy for repair period
- Rewind rotor
- Rewind exciter
- Dynamically balance rotor
- Remedial mechanical repairs as identified in Inspection Level 2
- Double impregnate and stove (rotor and stator)
- Epoxy coat windings
- Addition requested work
ALTERNATOR REPAIRS &
SERVICING FORM
Please click on the image to download and print our Rental Alternators Repairs & Servicing Form. Fill it out and attach it to your alternator before delivering it to our workshop.
