The 988K XE Caterpillar wheel loader has an electric drive system that uses the company’s switched reluctance technology. The power train incorporates a Cat C18 engine that drives a generator assembly, which includes an integral pump drive. Power from the generator is controlled via a liquid-cooled “integrated powered electronics” module that directs electrical power to a continuously variable electric motor that provides automatic retarding. The motor drives into a vertical gearbox, from which the machine’s standard 988K axles are driven. Bucket capacities range from 6.2 to 17 cubic yards, and a high-lift boom is available. The 988K XE increases efficiency by 25 percent overall, and by up to 49 percent in face-loading applications, as compared to the 988K.
The standard 988K XE is performance matched to offer efficient three-pass loading of the 42.6-ton Cat 770G haul truck and four-pass loading of the 51-ton Cat 772. The high-lift configuration can five-pass load the 61-ton Cat 773G and six-pass load the 70.5-ton Cat 775G.
The 988K XE’s electric drive technology, says the company, lowers overall maintenance costs, while increasing engine life expectancy. The engine’s extended oil-change interval (2,000 hours), says Caterpillar, results in the electric-drive machine using 40 percent less power-train oil. The switched-reluctance drive motor, generator, and inverter are built to last through a second engine life with minimum maintenance, says Caterpillar. In addition, says the company, the electric-drive design increases engine life by up to 3,500 hours, extending time between rebuilds.
Slight changes in the cab provide the 988K XE operator with the familiar functions and feel of the 988K, says Caterpillar, while also providing improved handling smoothness and ease of operation. The new loader has a single speed range, eliminating the need for gear shifting. “Virtual gears” are designed to help control machine ground speed and deliver smooth direction shifts.
The standard Cat Product Link telematics system offers remote data monitoring through VisionLink, allowing fleet managers to track machine operating data, such as fuel usage, payload summaries, scheduled service reminders, and fault-code alerts. Also, the onboard Vital Information Management System (VIMS) provides operating data, such as real-time fuel consumption and fuel efficiency, via an interactive touch screen display.
Other technology incorporated in the design of the 988K XE includes the Cat Production Measurement system, which, says the company, “brings payload weighing to the cab.” An optional tire-pressure-monitoring system enables operators to monitor tire inflation via the VIMS display.
The new loader has access via left- or right-hand stairs, built at a comfortable 45-degree angle, says Caterpillar. The STIC (Steering/Transmission Integrated Control) system’s armrest folds up to assist cab entry/exit, and isolation-type cab mounts and an air-suspension seat are designed to reduce transmitted vibration.
Cat 988K XE Specifications
- Engine: Cat C18 ACERT
- Gross power (SAE J1995): 588 horsepower
- Operating weight, standard: 116,362 pounds
- Operating weight, high lift: 119,618 pounds
- Rated payload, standard, face / loose: 12.5 tons / 16 tons
- Rated payload, high lift, (face / loose): 12.5 tons / 16 tons
- Bucket capacity range: 6.2-17 cubic yards
- Dump clearance, standard: 11.5 feet
- Dump clearance, high lift: 12.7 feet