Power Transformer Division
Red Metal Mining has been a trusted name in the cast resin transformer market since 2006, delivering quality-driven solutions across sub-Saharan Africa. In response to our clients’ growing demand for oil type transformers for both surface and underground applications, we expanded our capabilities in 2021 with the establishment of a dedicated oil transformer manufacturing facility.
Today, our RMM POWER TRANSFORMERS division plays a key role in our offering — focusing on the manufacture of oil type transformers and mini substations, meticulously engineered for durability, reliability, and high performance in the most demanding operational environments.
All manufacturing is done locally in South Africa, and we are a proud Level 4 B-BBEE contributor, committed to driving transformation, creating local employment, and delivering sustainable industrial power solutions throughout the region.
Product Range
Product range currently offered:
- Oil Type Transformers – In-House Range from 100kVA to 3150kVA In-House Operating voltages up to 33kV
Lead times based on your custom requirements Aluminium or Copper winding options Built in accordance with SANS780:Edition 4 / 5.1
All transformers are fully tested in our state-of-the-art testing facility and comply with the following standards:
- SANS 780
- IEC 60076
We offer our clients:
- Short delivery periods of approximately 6-8 working weeks depending on our manufacturing schedule
- Option of using copper or aluminum for the transformer windings
We have invested in the latest Solidworks 3D Mechanical software packages as well as EPLAN Software to provide detailed Schematic Drawings and 3D visualization of the terminal boxes and cable wiring.
Our product range includes:
- Cast Resin Dry Type Transformers 100kva to 20MVA –Manufactured in SA – High Quality IP00 Imports
- Underground Cast Resin Mini Substations – Manufactured in SA only Active Part Imported
- Oil Type Surface Mini Substations – Manufactured in SA
- Industrial Enclosures. Cast Resin Dry-Type Transformers (F1 rated, self-extinguishing)
- Oil Immersed Transformers- ONAN 100kVA to 3150kVA (max 33kV) Manufactured in SA
- Oil Immersed Power Transformers- ONAN 3150kVA to 200MVA (220kV) High Quality Import
- Oil Purification Services across South Africa
- Oil-cooled Transformer Repairs and Service
- Solar PV Transformers – Oil and DRY Type
- Large Electric Motors Imported from France 1000KW and above
- Power Factor Correction (electricity saving solutions) / Power Factor Analysis
- Power Factor Correction Panels + Power Quality Panels
- Data Centre Cast Resin Dry Type in IP 23/IP44 enclosure
- Data Centre Oil Type with radiators – Manufactured in SA
Recent Projects
2 x 315MVA Oil Cooled Surface Mini Substations Manufactured
RMM manufactured 2 x 315kva 11000v/400v oil type surface minisubs for a plant in Cape Town with positive feedback from the client. We take pride in excellent quality and after sales service to our clients and the project was completed on time.
1 x 1000mva Oil Cooled Transformer Manufactured
RMM manufactured its first oil cooled transformer in its new state of the art factory based in Chloorkop, Edenvale. The transformer rating is 1000kva 11000v/400v ONAN transformer. All routine tests were performed according to SANS 780.The client is well pleased with...
Testing
Routine testing on all transformers manufactured – SANS780 / IEC60076:
- Measurement of winding resistances
- Measurement of voltage ratio and check of phase displacement
- Measurement of impedance of the load and losses
- Measurement of no-load losses and no-load current
- Separate source AC withstand voltage test
- Measurement of insulation resistance
- Tank effectiveness of sealing the transformer
We use the following testing equipment – SANS 780:
- 560MVA Alternator set – 50Hz/100Hz (Dual Frequency)
- 500MVA Test transformer with varies voltages up to 33kV
- 100Kva 80Kv 400v Separate source single phase transformer
- Fluke 1777 Power Analyzer
- Clamp on Current Transformer (1730)
- BA80- 80Kv Portable Breakdown Analyzer for Oil Testing
- BK Precision 878B RCL Tester (Resistance, Capacitance and Inductance)
- TWA4OD 3 -Phase Winding Ohmmeters & Tap Changer % Winding Analyzers
- True 3-Phase transformers Turns Ratio Tester
- Fluke Multimeters
- Elcometer Dry Film Paint Thickness Tester
- MT95 -Sound Meter
Services
Oil type transformer repairs/rewinding – SANS 780/IEC 60076
We refurbish/rewind all exiting types of oil transformers and minisubs at our facility with full documentation and a 12-month warranty period from commission. The coils will be rewound on our winding machines and tested accordingly. All transformer tanks will be sandblasted in-house, as well as wet sprayed and baked in the spray booth located at our premises.
On-site Services
- Onsite Oil Purification: We also offer onsite oil regeneration/testing with our new oil purification plant mounted on a trailer to move to site. Our onsite team has years of experience and are well qualified and are available 24/7.
- Duty & Performance: We offer performance in a single pass through the purifier at full flow rate.
- Dielectric Strength: Improvement in dielectric strength up to 70kv with new oil.
- Water Removal: From 50ppm down to less than 50 ppm in a single pass and down to 3ppm after two passes as measured by the ASTM Method D-1533.
- Particulate removal: 98% of particles over 1 micrometer, or over 1 or 5 micrometers, as per your preference.
- Gas Removal: From fully saturated with air (10 to 12% by volume) down to less than 0.1% by volume as measured by ASTM Method D-2945.
- Design: Flow rate of 3000l/h with a vacuum booster for improved performance.
- Transformer Audits: Performed onsite on your existing transformers can be beneficial to the lifespan of your transformers by doing regular oil sampling tests. Written reports will be drafted on each units tested.
For sales enquiries or more information, please contact our sales team.
Contact details
+27 (0)11 794 9498
Projects Manager
Sales Executive