Buy new and second-hand SDMO generators – a wide selection of generators for construction sites, hire and emergency power, direct from specialist dealers. We stock used SDMO generators from the Rental series, ranging from R22 to R135, available either in soundproof enclosures or as mobile units on single-axle chassis. Each listing specifies the year of manufacture, power output in kVA and, where known, the operating hours. Supplied by Bontebok Trading from the Netherlands; stock changes regularly. You can also find stationary units under ‘Emergency Power Generators’ and ‘Generators’. SDMO, KOHLER-SDMO, KOHLER and Rehlko all refer to the same range of generators from Brest. The current name, Rehlko, has been in use since 2024.
SDMO at a glance
SDMO was founded in 1966 in Brest, Brittany. The Meunier family established the company to distribute marine engines; the name stands for ‘Société de Distribution des Moteurs de l’Ouest’. From 1969, SDMO began manufacturing its own generator sets, and in 1973 the head office and factory were established in Brest. In 1984–85, SDMO acquired Alstom’s AMAN generator set division and the switchgear specialist SOREEL. In the mid-1990s, a new 15,000 m² factory was built in the Brest industrial estate. Subsidiaries were also established in Spain, the UK, Singapore, South America and the USA.
In 2005, the family-owned holding company sold SDMO to the US group Kohler. In 2012, another plant, Kergaradec II, came into operation, bringing the total area of the main site to around 40,000 m². In 2016, the brand was renamed KOHLER-SDMO, and the KD series, featuring Kohler’s own engines, was launched at the same time. Since 2021, the generators have been marketed solely under the KOHLER name. In 2024, the private equity firm Platinum Equity acquired the energy division Kohler Energy, which has been known as Rehlko since September 2024. The EMEA headquarters is now located in Guipavas, near Brest, on a 42,800 m² site. According to the company, around 35,000 industrial and portable generators leave the factory every year, with the range spanning from 2 to 4,500 kVA.
The SDMO portfolio – new and used
The overview shows the equipment groups with the current model ranges now marketed under the Rehlko brand, as well as the models most frequently traded on the second-hand market. You can see which generators are currently on offer in the listings on this page.
| Unit type | Current model ranges (new) | Frequently traded second-hand | Available from us |
|---|---|---|---|
| Rental units up to 65 kVA | R20C5, R50C5 (Stage V) | R22, R33, R44, older R16 | Generators |
| Rental generators 66–250 kVA | R66C3, R110C3, R110C5, R165C3, R165C5, R220C5, R220RC | R110, R135, R220 | Generators |
| Rental generators over 250 kVA | R330C5, R550C5 | R275 | Power generators |
| Containerised generators | formerly Rental Power and CONTENERGY (650–2,800 kVA), up to 550 kVA in the current rental range | Occasional units of around 1,000 kVA with MTU engines | Generators |
| Industrial and emergency power generators | KD series (6–4,500 kVA), T, D, V and B series, small J and K units | J series with John Deere engine (e.g. J66K) | Emergency power generators, generators |
| Portable power generators | now marketed under the KOHLER brand, formerly Perform, Technic and Diesel Silence (3–14.4 kVA) | – | Power generators |
| Welding generators | formerly Weldarc 200 and Weldarc 220T | Weldarc 200 | Generators |
| Lighting masts | formerly RL10, RL4500-3 (LED), RL6 | – | Lighting masts |
What the SDMO model designation reveals
For rental generators, the system is simple: R stands for Rental, and the number indicates the standby power (ESP) in kVA. The continuous power (PRP) is around 10 per cent lower. An R135 therefore delivers 135 kVA standby and 123 kVA in continuous operation. This is why the same unit is sometimes advertised as 135 kVA and sometimes as around 120 kVA. The suffix indicates the model and emission standard. C3 denotes the EU model compliant with Stage IIIA, C5 the newer Stage V units, and RC units without EU emissions approval for markets outside the EU. According to the manufacturer’s 2017 catalogue, the R16 to R44 models are powered by Mitsubishi engines, the R66 to R330 models by John Deere engines, and the R450 and R550 models by Volvo engines. For industrial generators, the letter denotes the series; the J-series, for example, is fitted with John Deere engines. The type plate and the technical data sheet are the authoritative sources.
| Model | Power ESP / PRP | Engine (as of 2017) | Typical application |
|---|---|---|---|
| R22 | 22 / 20 kVA | Mitsubishi S4Q2 | Construction power for containers, small equipment and small building sites |
| R33 | 33 / 30 kVA | Mitsubishi S4S | Construction sites, events |
| R44 | 40–44 kVA | Mitsubishi S4S | Construction power supply with mixer, pumps and tools |
| R66 | 66 / 60 kVA | John Deere 4045 | medium-sized construction sites, temporary site power supply |
| R110 | 110 / 100 kVA | John Deere 4045 | Construction site with larger power consumers, emergency power backup |
| R135 | 135 / 123 kVA | John Deere 4045 | Larger construction sites, industrial sites and events |
| R165 / R220 | 165 / 150 and 220 / 200 kVA | John Deere 6068 | Large construction sites, temporary power supply during mains works |
| R275 / R330 | 275 / 250 and 330 / 300 kVA | John Deere 6090 | Industry, major events |
What we look for in a second-hand SDMO
Operating hours and maintenance: Rental generators are used extensively; several thousand hours are normal for equipment from the rental sector. Regular oil and filter changes, a clean cooling system and a complete maintenance record are crucial. Check that the hour meter matches the year of manufacture.
Generator and load test: Voltage and frequency should remain stable under load. Ideally, ask the supplier to demonstrate a load test using a load bank. Check the control panel, displays, emergency stop, sockets and terminal block, as well as the insulation resistance of the windings.
Cowl, fuel tank and sump: Inspect the sound-deadening mats, door seals and hinges on the housing; check the fuel tank and sump for leaks and rust. For mobile generators mounted on a chassis, the check should include brakes, lighting and registration documents.
Emissions standard and documentation: For construction sites in city centres and in the context of tenders, the emissions standard can be a deciding factor: C3 units comply with Stage IIIA, whilst C5 units comply with Stage V. RC models are not approved for the EU market. Ensure you are provided with CE documentation, the technical data sheet and the test certificate confirming compliance as portable electrical equipment in accordance with DGUV Regulation 3.
SDMO with us: dealers and stock
Bontebok Trading from the Netherlands stocks our entire range of SDMO products: used R22, R33, R44 and R135 rental generators manufactured between 2015 and 2018, as well as a 63 kVA generator on a single-axle chassis. You can find comparable generators under Himoinsa, Pramac and Atlas Copco; our full stock is listed in the ‘Generators & Power Generators’ category.
Frequently asked questions about SDMO power generators
Does SDMO still exist?
The generators are still manufactured in Brest; only the name has changed. Following the takeover by Kohler in 2005, they were known as KOHLER-SDMO from 2016 and as KOHLER from 2021. Since September 2024, the division has been part of Platinum Equity and is called Rehlko. Spare parts and servicing are handled via the Rehlko network.
What does the number in SDMO R22, R44 or R135 mean?
R stands for ‘Rental’, and the number indicates the standby power output in kVA. An R44 therefore delivers around 44 kVA in emergency power mode, whilst an R135 delivers around 135 kVA. The continuous power output is approximately 10 per cent lower in each case.
What is the difference between PRP and ESP?
PRP (Prime Power) is the power output for continuous operation with a varying load, for example on a building site. ESP (Emergency Standby Power) is the higher power output for limited emergency power applications. For site power, PRP is used as the basis for calculation.
What do C3, C5 and RC mean?
C3 stands for the EU version compliant with Emission Stage IIIA, whilst C5 refers to the newer units compliant with Stage V. RC generators are built for markets outside the EU and do not have EU emissions approval; you should bear this in mind when purchasing.
What engines are used in SDMO rental generators?
According to the 2017 manufacturer’s catalogue, the small Rental generators R16 to R44 have Mitsubishi engines, the medium-sized R66 to R330 have John Deere engines, and the large R450 and R550 have Volvo engines. This makes servicing and sourcing spare parts easier.
Which second-hand SDMO generators are most commonly traded?
On the second-hand market, the R22, R44 and R33 rental generators are among the most common models, followed by the R110, R135, R220 and R275. The choice is correspondingly wide.
How many operating hours are acceptable for a second-hand SDMO?
That depends on the engine and the maintenance history. Rental units with several thousand hours are common. More important than the number of hours are a complete maintenance log and a passed load test.
Can I lease an SDMO generator or finance it via hire purchase?
For many listings, you can submit a no-obligation enquiry about leasing or hire purchase directly. You can clarify the terms with the dealer or their finance partner; the purchase and payment are arranged directly between you and the seller.
An overview of all models: Construction machinery · Related products: Light poles, construction compressors, emergency power generators