The Könner & Söhnen KS 5500iES ATSR is a sound-insulated petrol inverter generator with a stable 230V pure sine wave output. It delivers 5.0kW rated power and 5.5kW maximum power, with electric and recoil starting, an ATS connection and parallel capability for flexible home-backup, workshop and mobile-power applications.
Free delivery to mainland Great Britain only.
At a glance
| Rated / maximum output | 5.0kW / 5.5kW |
|---|---|
| Output | 230V, 50Hz pure sine wave |
| Starting | Electric and manual recoil |
| AC sockets | 1 × UK 13A household socket; 1 × 32A Commando (CEE) socket — both 230V |
| Fuel tank / runtime | 13.5 litres; 8.4 hours at 50% load / up to 17 hours at 25% load |
| ATS / parallel | ATS output and generator parallel socket |
| Noise | 66dB(A) at 7m / 97dB(A) sound power |
| Net weight | 52kg |
Why choose the KS 5500iES ATSR?
- Pure sine wave inverter output: provides a stable 230V, 50Hz supply for compatible sensitive electronics and conventional appliances.
- 5.0kW rated output: supports substantial portable and backup loads while the sound-insulated enclosure helps reduce operating noise.
- Automatic backup capability: a 7-pin ATS socket supports the separately sold KS ATS 4/25 Inverter transfer switch.
- Parallel-ready: connect a compatible KS inverter generator using the included parallel cable to increase available output.
- Electric and recoil starting: offers convenient push-button starting with a manual-start alternative.
- Economy Mode: reduces engine speed at lighter loads to help lower fuel consumption and noise.
- Multifunction display: shows load, fuel level, voltage, frequency and working hours, with separate overload, voltage and oil-level indicators.
- Portable enclosure: integrated wheels and a telescopic handle help move the 52kg generator.
Power, fuel and connections
Plan loads around rated power
Use 5.0kW as the continuous rating and allow for appliance starting surges. The manual advises keeping prolonged loads within 80% of rated output — approximately 4.0kW — to support service life.
Petrol setup
Use unleaded petrol with an octane rating of 90–95 and no more than 10% ethanol. Add suitable four-stroke engine oil and connect the supplied battery terminals before the first electric start.
ATS and fixed wiring
Automatic start requires the separately sold KS ATS 4/25 Inverter unit. Any ATS connection, changeover equipment or connection to fixed wiring must be designed and installed by a suitably qualified electrician.
Technical specifications
| Voltage | 230V |
|---|---|
| Frequency | 50Hz |
| Rated output | 5.0kW |
| Maximum output | 5.5kW |
| Maximum current | 23.9A |
| Power factor | 1.0 |
| AC sockets | 1 × UK 13A household socket; 1 × 32A Commando (CEE) socket — both 230V |
| DC output | 12V / 8.3A |
| USB outputs | 5V / 1A and 5V / 2.1A |
| ATS connection | 7-pin output for KS ATS 4/25 Inverter |
| Parallel connection | Yes — parallel cable included |
| Fuel | Petrol |
|---|---|
| Engine | KS 330i, single-cylinder four-stroke, air-cooled |
| Engine capacity | 312cm³ |
| Engine power | 9.5hp |
| Starting | Electric and manual recoil |
| Fuel tank | 13.5 litres |
| Average runtime at 50% load | 8.4 hours |
| Runtime at 25% load | Up to 17 hours |
| Engine oil capacity | 0.85 litres |
| Starter battery | 1.6Ah lithium battery |
| Alternator winding | Copper |
| Emissions standard | EURO 5 |
| Net dimensions (L × W × H) | 610 × 470 × 535mm |
|---|---|
| Gross dimensions (L × W × H) | 680 × 510 × 605mm |
| Net weight | 52kg |
| Gross weight | 57.8kg |
| Sound pressure at 7m | 66dB(A) |
| Sound power | 97dB(A) |
| Protection class | IP23M |
What's included
- Spark plug wrench
- Filling funnel
- Parallel connection cable
- PH2 screwdriver, 6.0mm
- 32A Commando (CEE) plug
Engine oil, petrol and the external ATS unit are supplied separately.
Before first use
Connect the starter battery and add engine oil before starting. The generator is supplied with its battery disconnected and without engine oil or petrol. Connect the battery terminals with the correct polarity, add SAE 10W-30 or SAE 10W-40 four-stroke engine oil, check the oil level, add suitable petrol and open the fuel valve before starting.
Manuals and downloads
Warranty
Manufacturer's warranty: 1 year or 1,000 operating hours, whichever comes first, from the date of purchase.
The warranty covers manufacturing defects, subject to the manufacturer's warranty conditions. Eligible faults may be repaired or the product replaced. Retain your proof of purchase and any completed warranty documentation supplied with the generator.
For help with a warranty claim, contact Energian with your order number, generator serial number and a description of the fault.
Frequently asked questions
Can the KS 5500iES ATSR start automatically during a power cut?
Yes, when connected to the separately sold KS ATS 4/25 Inverter transfer switch through its 7-pin ATS socket. The ATS unit starts the generator and transfers the load when mains power fails, then stops it when mains power returns. Installation must be completed by a suitably qualified electrician.
Can it be connected in parallel with another generator?
Yes. The generator has a parallel socket and the parallel connection cable is included. Use only compatible KS inverter equipment and follow the owner's manual.
Is it suitable for sensitive electronics?
It produces a pure sine wave output designed for compatible sensitive electronics. Check each appliance's running and starting requirements and allow a suitable power margin.
How much power should I use continuously?
The rated output is 5.0kW. For prolonged operation, the manual recommends keeping the load within 80% of rated power, approximately 4.0kW.
Is engine oil included?
No. Add suitable SAE 10W-30 or SAE 10W-40 four-stroke engine oil before the first start and check the level before each use.
Energian support
For help choosing a generator contact Energian on 020 8064 0335 or info@energian.co.uk. For after-sales support, have your order number and generator serial number ready.