Specifications
| Fuel | NG/LP |
|---|---|
| Frequency | 60.0 Hz |
| Standby power | 20 kW |
| Prime power | 20 kW |
| Controller | Proprietary electronic |
| Oil capacity | 2.3 L |
| Alternator | 60 Hz, 1 phase, < 5% THD |
| Voltage options | 120/240 V |
| Phase | 1 |
| Rated current | 144/72 (NG), 162.5/81.25 (LP) A |
| Circuit breaker | 100 A |
| Battery group | 26R |
| Battery cranking | 530 CCA |
| Battery voltage | 12 V |
| Battery quantity | 1 |
| Dimensions (L×W×H) | 863×914×686 mm |
| Dry weight | 245 kg |
| Sound level | 62.0 dBA @ 7 m |
Filters & service parts
model family| Item | Spec | Capacity | Part # | Interval | |
|---|---|---|---|---|---|
| Air filter | Large-capacity air cleaner | — | |||
| Fuel filter | — | ||||
| Oil filter | Spin-on oil filter | — | |||
| Battery | 12 V, group 26R, 545 CCA Maintenance Free | — | |||
| Belt | — | ||||
| Coolant | — | ||||
| Oil | Cummins Proprietary electronic control with self-diagnostics and generator set protection and safety features included | 2.3 L | — | 2000 hr | |
| Spark plug | — |
Compiled from this model's family documentation — may include parts for closely-related variants. Confirm the exact part for your serial number.
Service specifications
2| Type | Item | Value | Unit | Condition |
|---|---|---|---|---|
| Pressure | Fuel supply pressure (LP) | 7-11 | in H2O | |
| Pressure | Fuel supply pressure (Natural gas) | 5-11 | in H2O |
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
Recommended fluids
| Fluid | Grade | Standard | Ambient | Capacity | Notes |
|---|---|---|---|---|---|
| Engine oil | Automotive-style lubrication system | -7°C to 50°C | 2.3 L | Oil cooler and spin-on filter included |
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
Voltage reconnection
| Voltage | Phase | Connection | Leads | Notes |
|---|---|---|---|---|
| 115/230 | 1 | Split phase | Available on RS14AF model at 50 Hz | |
| 120/240 | 1 | Split phase | Available on RS20A and RS20AC models at 60 Hz |
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
Common questions
How many kW is the Cummins/Onan RS20A?
The Cummins/Onan RS20A is rated 20 kW standby.
What engine does the Cummins/Onan RS20A use?
The Cummins/Onan RS20A is powered by the Cummins/Onan QSJ999G engine.
What fuel type does the Cummins/Onan RS20A take?
The Cummins/Onan RS20A runs on NG/LP.
What is the oil capacity of the Cummins/Onan RS20A?
The Cummins/Onan RS20A has an engine oil capacity of 2.3 liters (2.4 US quarts), per the manufacturer specification sheet.
How loud is the Cummins/Onan RS20A?
The Cummins/Onan RS20A is rated at 62.0 dBA at 7 m, per the manufacturer specification sheet.
What is the dry weight of the Cummins/Onan RS20A?
The Cummins/Onan RS20A has a dry weight of 245 kg (540 lb).
What voltages is the Cummins/Onan RS20A available in?
The Cummins/Onan RS20A is offered in 120/240 V, 1-phase.
What battery does the Cummins/Onan RS20A use?
The Cummins/Onan RS20A uses 1 battery, 12 V each, 530 CCA, group 26R, per the manufacturer specification sheet.
What alternator comes on the Cummins/Onan RS20A?
The Cummins/Onan RS20A uses a 60 Hz, 1 phase, < 5% THD alternator.
Fuel consumption
| Rating | Load | L/h | gal/h |
|---|---|---|---|
| Continuous | 25% | 3.79 | 1.0 |
| Continuous | 50% | 5.5 | 1.5 |
| Continuous | 75% | 7.8 | 2.1 |
| Continuous | 100% | 11.4 | 3.0 |
| Prime | 228.0 | 83.0 | |
| Prime | 25% | 6.06 | 1.6 |
| Prime | 50% | 7.95 | 2.1 |
| Prime | 75% | 10.22 | 2.7 |
| Prime | 100% | 12.87 | 3.4 |
| Standby | 25% | 14.76 | 3.9 |
| Standby | 50% | 18.17 | 4.8 |
| Standby | 75% | 21.2 | 5.6 |
| Standby | 100% | 26.12 | 6.9 |
Available documents
This page was generated from the 5 manufacturer documents above by automated extraction; every figure shown is copied from one of them. How the data is compiled.