PGE has two Cummins DQGAA / QSK50 1250kW Tier 2 diesel generator sets in stock right now. The primary unit is SKU GS4868 — pre-owned, approximately 100 hours, weather enclosed and sound attenuated, rated 1250kW standby / 1100kW prime, 480V/3-phase/60Hz, powered by a QSK50-G4 NR2 engine with a 2500-gallon base fuel tank. We also carry GS4860, an open-skid DQGAA at $185,000. View full specs, photos, and pricing on the GS4868 product page, or call PGE at (818) 484-8550. We ship from Santa Clarita, CA.
The unit sitting in PGE’s Santa Clarita yard right now — SKU GS4868 — is a Cummins DQGAA generator set with approximately 100 hours on the clock. That is barely broken in for an engine that Cummins builds to run 20,000+ hours between major overhauls.
The DQGAA is Cummins’ factory-integrated 1250kW standby package built around the QSK50-G4 NR2 diesel engine. The QSK50 is a V16, 50.3-liter displacement, turbocharged and aftercooled platform with a square bore and stroke of 159mm x 159mm. At 1800 RPM and 60Hz, it produces 1250kW standby and 1100kW prime. The engine uses Cummins’ modular common rail fuel system — not the older PT fuel system found on KTA50-series units — which means tighter injection timing control, lower emissions, and better fuel economy across the load range.
This specific GS4868 unit includes:
The weather enclosure on the GS4868 is a significant feature. Open-skid units in this power class are cheaper — PGE’s GS4860 is an open-skid DQGAA at $185,000 — but outdoor installations without an enclosure require a building or canopy, which adds $40,000-$80,000 in construction costs and months of lead time. The enclosed GS4868 drops on a concrete pad and connects. For data centers, hospitals, water treatment plants, and manufacturing facilities that need fast deployment, the enclosed configuration eliminates a major project bottleneck.
The “NR2” designation on the QSK50-G4 engine means EPA Tier 2 non-road emissions compliance. In practical terms: no diesel particulate filter (DPF), no selective catalytic reduction (SCR), no diesel exhaust fluid (DEF). The exhaust system is a straight pipe with a muffler. For standby and prime power applications where Tier 4 is not mandated by your AHJ, this is a maintenance advantage that compounds over the life of the unit. You will never deal with a clogged DPF, a failed DEF injector, or an SCR catalyst replacement that costs $15,000-$25,000 on a Tier 4 Final unit in this power class.
PGE published a full Cummins QSK60 generator guide covering the 2000kW DQKAB/DQKAC platform. The QSK60 is the right unit when you need 1500-2000kW. But a lot of buyers spec a QSK60 when a QSK50 would have been the correct call, and they pay for it every year they own the unit.
The QSK60 is a V16 with 60.2 liters of displacement. The QSK50 is also a V16 with 50.3 liters. Same cylinder count, same basic architecture, but the QSK60 requires 280 liters of oil versus the QSK50’s 235 liters. That oil change cost difference — roughly $800-$1,200 per service event depending on your oil program — adds up over a 20-year service life with changes every 250-500 hours of runtime.
Fuel consumption scales roughly with displacement. A QSK60 at 75% load burns more fuel per hour than a QSK50 at 100% load producing the same kW output. If your actual demand sits between 800kW and 1100kW, the QSK50-based DQGAA runs at a more efficient loading percentage than an oversized QSK60 loafing at 40-55%.
There is also a footprint consideration. The DQGAA is physically smaller and lighter than the DQKAB/DQKAC. If you are replacing an existing unit or fitting into a constrained pad, the QSK50 package can be the difference between a direct swap and a civil engineering project.
Where the QSK60 wins: if your peak demand exceeds 1250kW or you need the prime continuous rating above 1100kW for extended run applications. If your load study shows consistent demand above 1000kW with peaks approaching 1500kW, spec the QSK60. If your peaks are 1250kW or less and your average sits around 700-1000kW, the DQGAA with the QSK50 is the better machine for your application and your operating budget.
The other unit buyers cross-shop against the QSK50 DQGAA is the Caterpillar 3512-series, and PGE carries both. Our CAT 3512 guide covers the full 3512 lineup in detail.
The comparison comes down to this: the CAT 3512B and 3512C are typically rated 1000-1360kW depending on configuration. The Cummins QSK50 DQGAA sits at 1250kW standby. In the overlap zone between 1000-1250kW, here is what separates them.
Parts and service network. Caterpillar and Cummins both have dense dealer networks in North America. CAT edges Cummins slightly in total dealer locations. Cummins edges CAT in parts availability for the QSK50 specifically because the QSK50 shares cylinder kits, liners, injectors, and many rotating components with the smaller QSK45 and the larger QSK60. Buying parts for a QSK50 draws from a broader family parts pool than a 3512-specific order.
Fuel system complexity. The QSK50-G4 uses a modular common rail system. The CAT 3512B uses MEUI (Mechanically-actuated, Electronically-controlled Unit Injection), and the 3512C uses HEUI on some variants. The Cummins common rail is a newer architecture that is generally easier to diagnose and service, though CAT MEUI injectors are extremely durable and field-rebuildable.
Control system. The DQGAA ships with Cummins PowerCommand. CAT 3512 packages ship with EMCP (Electronic Modular Control Panel). Both are mature, reliable platforms. If your facility already has other Cummins or CAT units, matching the control platform simplifies paralleling and operator training.
Resale value. CAT generators hold a slightly higher resale percentage than Cummins in the secondary market — CAT brand loyalty runs deep. But the QSK50 DQGAA is not a common unit on the used market. When one shows up with 100 hours like PGE’s GS4868, it does not sit long.
| Unit / SKU | Engine | kW / Voltage | Enclosure / Tier | Why Consider This One |
|---|---|---|---|---|
| Cummins DQGAA (GS4868) | QSK50-G4 NR2 | 1250kW / 480V | Weather Enclosed / Tier 2 | ~100 hours, enclosed with 2500-gal tank — turnkey deployment |
| Cummins DQGAA (GS4860) | QSK50-G4 NR2 | 1250kW / 480V | Open Skid / Tier 2 | $185,000 — best value at 1250kW if you have an enclosure or building |
| Cummins DQFAD (GS4833) | QST30 | 1000kW / 480V | Open Skid / Tier 2 | $159,000 — step down to 1000kW on the proven QST30 platform |
| MTU 1000DSEC (GS4844-1) | MTU 16V2000 | 1000kW / 480V | Weather Enclosed / Tier 2 | $149,000 — enclosed 1000kW at the lowest price point in stock |
| MTU 1000DSEC (GS4823) | MTU 16V2000 | 1000kW / 480V | Open Skid / Tier 2 | $130,000 — two available, open-skid MTU for budget-conscious projects |
| NEW Cummins QST30 (GS4829) | QST30 | 1000kW / 480V | Open Skid / Tier 4 Final | $275,000 — brand new with full Cummins warranty, Tier 4 compliant |
Used Cummins QSK50 generator pricing on the secondary market ranges from roughly $120,000 for a high-hour open-skid unit to $350,000+ for a low-hour enclosed package with a sub-base fuel tank. New DQGAA packages from Cummins distributors currently list $450,000-$600,000+ depending on enclosure and options, with lead times of 16-28 weeks.
The price spread on used QSK50 units comes down to five variables:
Hours. A QSK50 with under 500 hours — like PGE’s GS4868 at approximately 100 hours — commands a premium because the engine has essentially its entire service life ahead of it. Units with 5,000-10,000 hours are approaching the first top-end service interval. Units above 15,000 hours need an overhaul cost factored into the purchase price.
Enclosure. Weather enclosed, sound attenuated units sell for $40,000-$80,000 more than equivalent open-skid units. Compare PGE’s enclosed GS4868 to the open-skid GS4860 at $185,000. The enclosure premium reflects the real cost of building or buying a weather enclosure separately.
Fuel tank. The GS4868 includes a 2500-gallon base fuel tank — a $15,000-$25,000 option that also eliminates the need for a separate day tank or external fuel storage for many applications.
Emissions tier. Tier 2 units like both of PGE’s QSK50 sets are the most popular in the secondary market because they have no aftertreatment. Tier 4 Final QSK50 units carry higher list prices new but can actually sell for less used in markets where Tier 2 is acceptable, because the Tier 4 aftertreatment adds maintenance burden.
Controller generation. The PowerCommand 3201 is the standard on DQGAA packages. Earlier PowerCommand 1301 or 2100 controllers are functional but lack some of the remote monitoring and paralleling features. The 3201 supports Ethernet connectivity, load sharing, and ATS integration out of the box.
If you are buying a used QSK50, PGE’s pricing on the GS4868 reflects the reality that you are getting a unit with the equivalent of a new engine, a factory enclosure, and a 2500-gallon fuel tank for roughly half of what a new DQGAA package costs with a six-month wait. Call (818) 484-8550 to discuss pricing on either unit.
The QSK50 follows Cummins’ standard standby generator maintenance schedule. Here is the timeline that matters for ownership cost planning:
Every 250 hours or annually (whichever first): Oil and filter change, coolant check, belt inspection, battery test. Budget $1,500-$2,500 per service depending on oil volume and filter costs. The QSK50 takes approximately 62 gallons (235 liters) of oil.
Every 1,500 hours: Fuel filter replacement, valve lash adjustment, coolant sample analysis. Add $800-$1,200 to the standard service.
Every 6,000 hours: Top-end inspection — injectors, turbocharger, aftercooler core. This is where you decide if injectors get rebuilt or replaced. Injector rebuild kits for the QSK50 run $400-$600 per cylinder, times 16 cylinders. Budget $15,000-$25,000 for a comprehensive 6,000-hour service.
Every 12,000-20,000 hours: Major overhaul — pistons, liners, bearings, oil pump, water pump, turbo rebuild. A full QSK50 in-frame overhaul runs $80,000-$120,000 depending on parts condition and whether you use genuine Cummins parts or aftermarket. Out-of-frame rebuilds can reach $150,000+.
For standby applications running 100-200 hours per year, you are looking at one oil change annually and a major overhaul roughly never — or at least not for 60-100 years at that run rate. The GS4868 with 100 hours could run as a standby unit for decades before the engine needs serious attention.
For prime power applications running 4,000-6,000 hours annually, the QSK50 delivers a cost-per-kWh that competes favorably with both the CAT 3512 and smaller multi-unit configurations. The key advantage is parts commonality within the Cummins QSK family — liners, pistons, and injector components are shared across the QSK45, QSK50, and QSK60, which keeps parts pricing competitive and availability strong through the Cummins dealer network.
PGE provides full maintenance history documentation on every unit we sell. On the GS4868, that means the complete service record from commissioning through its current 100-hour status. Call (818) 484-8550 to request the maintenance package, or view the full listing with photos here.
PGE maintains one of the largest inventories of 1000-1250kW diesel generators in the western United States. In addition to the two Cummins QSK50 DQGAA units featured in this guide, here is what we have on hand right now in this power range. See the comparison table below for a side-by-side, or browse our full Cummins generator inventory.
If none of these units match your spec, PGE sources specific configurations through our nationwide dealer network. We also buy industrial generators — if you have a unit to trade or sell your equipment to offset the purchase, contact us at (818) 484-8550.
The Cummins QSK50 has a major overhaul interval of 12,000-20,000 hours depending on loading, maintenance program, and fuel quality. In standby service running 100-200 hours per year, the engine can operate for decades before a major overhaul. PGE’s GS4868 has approximately 100 hours — essentially a new engine with its full service life ahead of it. Call PGE at (818) 484-8550 for the complete maintenance history.
The Cummins DQGAA with the QSK50-G4 engine consumes approximately 85-90 gallons per hour at 100% load (1250kW standby). At 75% load it drops to approximately 65-70 GPH, and at 50% load roughly 45-50 GPH. The GS4868 unit in PGE’s inventory includes a 2500-gallon sub-base fuel tank, providing over 27 hours of runtime at 75% load without refueling. View the full GS4868 specs and fuel tank configuration.
No. The QSK50 replaced the KTA50 in Cummins’ lineup. Both are V16, 50-liter platforms, but the QSK50 uses a modular common rail fuel system instead of the KTA50’s PT (pressure-time) fuel system. The QSK50 also has an updated block casting, improved piston design, and electronic controls. The QSK50 is a more fuel-efficient, lower-emissions, and electronically sophisticated engine. PGE carries QSK50-powered generators including the DQGAA GS4868 — call (818) 484-8550 with questions about the QSK vs KTA platform differences.
Yes. The Cummins DQGAA with PowerCommand 3201 controller supports paralleling out of the box. Two QSK50 units in parallel give you 2500kW of standby capacity with N+1 redundancy if you size the load appropriately. PGE has GS4868 (enclosed) and GS4860 (open skid) available — two matching QSK50 DQGAA units that could be paralleled. Call (818) 484-8550 to discuss paralleling configurations.
At 1250kW, the Cummins DQGAA competes directly with the CAT 3512C (typically 1000-1360kW) and Kohler large-frame units. The DQGAA’s advantage is the QSK50 engine’s parts commonality with the QSK45 and QSK60, which keeps long-term parts costs competitive. CAT 3512-series generators hold slightly higher resale values due to brand loyalty. Kohler large-frame units use MTU engines, adding a second OEM to the parts equation. PGE carries all three brands — browse our Cummins inventory, read our CAT 3512 guide, or call (818) 484-8550 for a direct comparison.
Yes. PGE load tests every generator at our Santa Clarita, CA facility (26764 Oak Ave, Santa Clarita, CA 91351) before shipping. Buyers can attend the load test in person or request a video walkthrough. On the GS4868 QSK50, we verify output at 25%, 50%, 75%, and 100% load steps, check all fluid levels, confirm controller operation, and document the results. Call (818) 484-8550 to schedule an inspection or load test.
The Cummins DQGAA QSK50 1250kW Tier 2 diesel generator set — SKU GS4868 — is at PGE’s Santa Clarita facility with approximately 100 hours, a weather enclosure, sound attenuation, and a 2500-gallon sub-base fuel tank. We also carry the open-skid GS4860 at $185,000. Low-hour enclosed QSK50 units do not last on the secondary market. View the full listing with photos and specs, or call PGE at (818) 484-8550 to schedule an inspection or load test.
