Cummins QuietConnect RS20AC 20kW with 200A ATS vs Kohler 20RCAL 20kW with ATS
Both units carry the same best-fuel running rating: 20,000 W. The Cummins QuietConnect RS20AC 20kW with 200A ATS is the quieter of the two (65 dBA vs 69 dBA — though manufacturers measure noise at different loads and distances).
| Cummins QuietConnect RS20AC 20kW with 200A ATS | Kohler 20RCAL 20kW with ATS | |
|---|---|---|
| Type | home-standby | home-standby |
| Fuel | natural-gas, propane | natural-gas, propane |
| Running watts (gas / LP for standby) | 20000 W | 20000 W |
| Running watts (propane) | 20000 W | 20000 W |
| Running watts (natural gas) | 18000 W | 18000 W |
| Noise level | 65 dBA | 69 dBA |
| Output voltage | 120/240V | 120/240V |
| Automatic transfer switch included | Yes | 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 | 172 ft³/h | 161 ft³/h |
| Propane use at half load | 1.81 gal/h | 2.25 gal/h |
| Weight | 596 lb | 555 lb |
| Warranty | 5 yr | 5 yr |
Frequently asked questions
Which costs less to run, the Cummins QuietConnect RS20AC 20kW with 200A ATS or the Kohler 20RCAL 20kW with ATS?
Estimated fuel for 24 hours at about 50% load: $62 on natural gas for the Cummins QuietConnect RS20AC 20kW with 200A ATS 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.