The Atlas Copco QAS 25 ID T4F generator is prime power, multi-voltage, sound attenuated, mobile generators. It is powered by an Isuzu Tier 4 Final, liquid-cooled, four-cylinder diesel engine.

The units consist of an alternator, diesel engine, cooling system, electrical distribution and control systems - all enclosed within a sound attenuated enclosure fabricated from powder coated galvannealed steel. A broad range of undercarriage formats and options are available. Special attention has been given to the overall product quality, user friendliness, ease of serviceability, and economical operation to ensure best in class total cost of ownership.

View and/or Download QAS 25 JD T4F: Datasheet / Brochure


  • Compact, sound attenuated, corrosion resistant enclosure with single point lifting and 110% fluid containment
  • Available as a skid mounted unit with forklift pockets, or on a single axle trailer
  • Heavy Duty alternator with AREP excitation and marine grade protection
  • DeepSea controller
  • Single side servicing with long run filters and 500-hour service intervals
  • Isuzu 4LE engine w/EGR& DOC after-treatment and limited 5-year warranty
  • Identical enclosures and maintenance points between both models
  • Emergency Stop
  • Remote Start / Stop


  • Extremely durable and environmentally sensitive designed to be used for everything from the oil patch to special event power
  • Versatility, giving you the flexibility to match your machine to the correct application
  • Start-up power for the most demanding sites with 300% over load starting capabilites
  • Reliable and intuitive controls for ease of use and diagnostic capabilities
  • Reduced total cost of ownership with easy access for mechanics
  • Proven engine platform with high reliability, a simple maintenance free Diesel Oxidization Catalyst onlyafter treatment
  • Reduces stock of service kits and inventory of parts withrental ROI kept in mind
  • External, recessed emergency stop for increased safety
  • Allows connection as a critical back-up unit via a 2 wire dry contact connection in the distribution panel


Performance  Units QAS 25 JD 
Frequency  Hz  60 
Rated prime power 3ø  kW/kVA  20/25 
Rated standby power 3ø  kW/kVA  22/28
3ø Power factor    0.8 
3ø Voltage in 480V switch position (series star w/neutral)  480Y / 277 
Amp capacity @480V  30 
3ø Voltage in 240-208V switch position (parallel star w/neutral)  240YY / 139-208YY 

Rated Prime Power @ 240V 3Ø


Amp capacity @240V  60 

Rated Prime Power @ 2080V 3Ø


Amp capacity @208V  63 
Rated prime power 1ø  kW/kVA  13/13 
1ø Power factor   
1ø Voltage in 120-240V switch position (Zig-Zag)  240 / 120 
Amp Capacity @240V  54 
Amp Capacity @120V  54 x 2 
Alternator (4 Pole, 12 Wire) Leroy Somer LSA 40 M5
Excitation system   AREP (auxiliary winding)

Digital Automatic Voltage Regulator (+/- 0.25%)

Leroy Somer D350
Insulation   Class H
Main Breaker - Shunt Trip A 63
Power Distribution – Terminal Board   5 Wire (L1, L2, L3, N, Ground)
Terminal Board Connections   Bare Wire Terminals
Maximum Terminal Cable Size   350MCM
Convenience Receptacles   2 x NEMA 5-20R & 2 x 125/250V 50A CS6364
Engine  Units QAS 25 JD
Model    4LE2T
US EPA Family   


US EPA Tier    Tier 4 Final
Displacement  L 2.2 
Cylinders  # 4
Continuous engine output  HP (kW) 31.5 (23.5)
Gross engine power output  HP (kW) 40 (30)
Rated Speed RPM 1800
Engine control    ECU
Aspiration    Turbocharged
Engine oil capacity  US gal 1.9 (7.2)
Engine coolant capacity  US gal 3 (11.4)
Max. ambient temperature (@Sea Level) 

°F (°C)

Min. starting temperature

°F (°C)

Electrical system (Negative ground)  V 12
Engine alternator output  A 50
Battery Capacity (Cold Cranking Amps)  A 685
Sound Pressure Level @ 23’(7 m) @ 75% Load dB(A) 67

Fuel System  Units QAS 25 JD
Fuel Consumption @ 25% load Gal/hr (L/hr) 0.71 (2.69)
Fuel Consumption @ 50% load Gal/hr (L/hr) 1.02 (3.86)
Fuel Consumption @ 75% load Gal/hr (L/hr) 1.40 (5.30)
Fuel Consumption @ 100% load Gal/hr (L/hr) 1.63 (6.17)
Fuel Type   Ultra-Low Sulfur Diesel ONLY
Fuel Tank Capacity Gal/hr (L/hr) 75 (284)
Fuel Autonomy @ 75% load Hr 48.2

Applications & Use Cases


These light pneumatic rock drills have been designed especially for the dimension stone industry, drilling holes of 27-41 mm.

During the mining process, machines such as excavators, drillers, cranes, and conveyor belts use a lot of electricity. No matter what type of mining is taking place, Atlas Copco's QAS 25 diesel generator is the best choice as it is portable and can be utilized in remote and extreme mining zones.


Atlas Copco Portable Energy - DSC 0104

Outdoor events with big tents, lighting and all sorts of machinery running from vendors will require power from a mobile generator. Atlas Copco’s QAS 25, 45 or 70 diesel generators are a great fit for events as they are silent, compact and towable. There are also convenience receptacles as standard to use in single phase 120V outlets, California style 240V outlets, or Camlocks as an option.


Construction site with QAS 40 and XAS 97

During construction at remote sites, the power supply from a mobile diesel generator is essential. Because our QAS 25, 45, and 70 models are mobile and compact, construction crews rely on them for power during the whole project due to its reliability and transportability.

Applications & Use Cases

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