Cummins QuietConnect RS17A 17kW vs Kohler 20RCAL 20kW with ATS
The Kohler 20RCAL 20kW with ATS is the more powerful unit: 20,000 running watts against 17,000 — about 15% more capacity for the Kohler 20RCAL 20kW with ATS. The Cummins QuietConnect RS17A 17kW is the quieter of the two (65 dBA vs 69 dBA — though manufacturers measure noise at different loads and distances).
| Cummins QuietConnect RS17A 17kW | Kohler 20RCAL 20kW with ATS | |
|---|---|---|
| Type | home-standby | home-standby |
| Fuel | natural-gas, propane | natural-gas, propane |
| Running watts (gas / LP for standby) | 17000 W | 20000 W |
| Running watts (propane) | 17000 W | 20000 W |
| Running watts (natural gas) | 17000 W | 18000 W |
| Noise level | 65 dBA | 69 dBA |
| Output voltage | 120/240V | 120/240V |
| Automatic transfer switch included | No | Yes |
| Main-line circuit breaker | 100 A | — |
| Start type | automatic | automatic |
| Engine | Cummins QSJ999G | Kohler CH1000 |
| Engine displacement | 999 cc | 999 cc |
| NG use at half load | 165 ft³/h | 161 ft³/h |
| Propane use at half load | 1.73 gal/h | 2.25 gal/h |
| Weight | 531 lb | 555 lb |
| Warranty | 5 yr | 5 yr |
Frequently asked questions
Which is more powerful, the Cummins QuietConnect RS17A 17kW or the Kohler 20RCAL 20kW with ATS?
The Kohler 20RCAL 20kW with ATS, at 20,000 running watts on its best fuel versus 17,000 W. Remember that dual-fuel and natural-gas ratings are lower than gasoline ratings — the comparison table shows the published per-fuel figures.
Which costs less to run, the Cummins QuietConnect RS17A 17kW or the Kohler 20RCAL 20kW with ATS?
Estimated fuel for 24 hours at about 50% load: $59 on natural gas for the Cummins QuietConnect RS17A 17kW vs $58 on natural gas for the Kohler 20RCAL 20kW with ATS, at national average prices. These are spec-sheet-derived estimates — the assumptions are on the methodology page, and different fuels make this a cost comparison, not an efficiency ranking.
Where do these specifications come from?
Every record on BackupAtlas is hand-curated from manufacturer documentation and spec sheets, and each generator page links to its source document.