Overview#
The Blue Star NG500-01 is a 500-kilowatt natural gas / LP standby generator built on the PSI 32-liter V12 platform. It is rated 500 kWe standby on natural gas and 400 kWe on LP at 60 Hz / 1800 RPM. The NG500-01 introduces a larger engine family — the PSI 32L — with a correspondingly larger 210×96×103 in footprint and extended deration thresholds compared to the 21.9L-based models below 500 kW.
The PSI 32L V12#
The PSI 32L is a 31.8-liter (1,941 cu in) V12 turbocharged-aftercooled spark-ignition engine:
- 966 bHp (721 kWm) at 1800 RPM standby — 41% more power than the 21.9L platform
- 5.91-in bore × 5.91-in stroke — larger than the 21.9L's 5.04×5.59 in
- Extended deration tolerance: full output to 97°F inlet air temperature and 4,200 ft altitude
- Large cooling system: 361 GPM water pump flow (vs. 151 GPM on 21.9L), 54.4 gal system coolant
- EPA Stationary Spark Ignition certified under 40 CFR 60 Subpart JJJJ
Platform transition from 21.9L#
The NG500-01 represents a significant platform change from the NG450-01:
| NG450-01 (21.9L) | NG500-01 (32L) | |
|---|---|---|
| Engine | PSI 21.9L V12 | PSI 32L V12 |
| OPU dimensions | 156×86×98 in | 210×96×103 in |
| Dry weight | 10,875 lbs | 15,500 lbs |
| Deration start | 77°F / 1,200 ft | 97°F / 4,200 ft |
| Oil capacity | 10.6 gal | 32.2 gal |
| Water pump | 151 GPM | 361 GPM |
Alternator configurations#
| Voltage | Phase | Alternator | Connection |
|---|---|---|---|
| 120/208V | 3 | Stamford HCI534E | 12-lead WYE |
| 240V | 3 | Stamford HCI534E | 12-lead DELTA |
| 277/480V | 3 | Stamford HCI534D | 12-lead WYE |
| 347/600V | 3 | Stamford HCI534D | 4-lead WYE |
All configurations carry 125°C standby temperature rise and ±0.5% voltage regulation.
When to spec the NG500-01#
- 425–500 kW standby loads on natural gas or LP (three-phase only)
- Hot climate or high-altitude sites where the PSI 32L's extended deration (97°F / 4,200 ft) is the deciding factor
- Facilities with high LP output requirements — the 400 kWe LP standby rating is the best LP-to-NG ratio in the 500-class
Our service experience#
The PSI 32L V12 is a larger and less common platform than the 21.9L in most service territories. The oil system is significantly larger (32.2 gal), and the cooling system volume (54.4 gal system coolant) means more fluid to manage at maintenance intervals. The DSE DCP7310 controller is identical across the NG500 family, keeping service procedures consistent with other Blue Star gaseous units.
