Caterpillar’s revised lineup of 20-24-ton E Series crawler excavators, the 320E, 323E, and the reduced-radius 320E RR, adopt the EU Stage IIIB Cat C6.6 ACERT engine, providing reduced emissions and fuel consumption savings of up to 11%, compared to comparative D Series models, while providing fuel savings of 8% and 9% respectively.

The two conventional bodied models, along with the reduced radius 320E RR, are powered by a Cat C6.6 ACERT diesel engine. Rated power is 152 hp for the two 320E models and 165 hp for the larger 323E. This engine uses the Cat Electronic Control Module (ECM) in combination with the Cat Clean Emission Module (CEM) to meet the EU Stage IIIB emissions standards. The CEM incorporates a diesel oxidation catalyst (DOC), a diesel particulate filter (DPF), and a passive regeneration system that automatically cleans the DPF throughout the working cycle of the machine without requiring operator intervention or disruption to operations.

On the 320E and the 320E RR, the power management system provides two operating modes for the operator, high power and economy. On the 323E, a third middle mode is offered. An isochronous engine speed control ensures that the engine speed remains constant regardless of hydraulic demand. It also reduces idle speed under no load, reducing fuel consumption.

The three excavators feature an automatic engine idle shutdown system that will shut the engine down when it has been idling for more than a customer-specified amount of time. This idle period can be set between 1-60 minutes. In addition, an automatic engine speed control reduces engine revs by 100 rpm when the machine is not under load for more than five seconds, helping to save fuel and cut emissions.

The fuel system on the C6.6 ACERT is equipped with an electronically-controlled high pressure fuel injection system, featuring three-layer hoses, making it capable of running on bio-diesel up to a 20% mixture (EN 14214 or ASTM 6751) without additional adjustment.

The E Series engine cover uses lighter-weight composite materials to allow for easy opening. Service access doors have also been changed and are now lighter and stronger on the E Series excavator, thanks to a layered steel design. This eliminates weld spots on the surface of the machine. Revised venting holes eliminate the need for an internal debris screen. Major service items can be reached from ground level on all three machines, and the cooling pack has been revised to make cleaning easier.

Anti-skid plates are fitted to all surfaces on the machines’ upper structures to help prevent accidents during maintenance. Moreover, additional handrails and guardrails have been fitted to meet the ISO 2867 (2011) standard. The Cat Product Link monitoring system is available on the three E Series models, providing machine operation data, such as fuel use, idle time, location, and diagnostic codes direct to the operator through the VisionLink Web application.