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Hitachi is by no means the only manufacturer launching new mid-range excavators this spring. In fact the opposite is true. The introduction of US Tier 3 and European Stage IIIA diesel engine exhaust emissions laws for 130 to 560 kW units means pretty much every manufacturer in the world is launching new 25 tonne+ excavators at the moment.

Tier 3/Stage IIIA of course means new technology in the engine compartment, but the first of Hitachi's Zaxis-3 models, the 25 tonne class Zaxis 250-3, 28 tonne 280 and 35 tonne 350, also include significant advances in other parts of the package. A clever hydraulic system has been developed to speed-up stick and boom movements, and operator comfort is enhanced with more leg room and air conditioning as standard.

Other standard features include a GPS tracking and monitoring device – again only available as an optional extra on many machines – and an innovative rear-view camera on top of the counterweight.

Hitachi Construction Machinery (Europe) general manager for international sales, Paul Burger explained, “The rear view camera switches on to the in-cab LCD display automatically when the machine is moving. You can also chose and change the angle.”

Performance

Hitachi has chosen Isuzu engines to power the Zaxis-3 series, a 132 KW unit for the 250, 140 kW for the 280 and 202 kW for the 350. These units use common rail fuel injection systems and exhaust gas recirculation (EGR) to achieve compliance with the Stage IIIA laws.

According to Hitachi, the new machines are +10% to +17% more productive than their predecessors thanks to the combination of these engines and the company's own HIOS III hydraulic system. This clever design directs oil through both the boom and stick cylinders when both are being operated, without a return trip to the pump in between.

Hitachi says recirculating the oil around the arm in this way can speed up digging cycles by as much as +15%.

Overall Hitachi claims a -15% reduction in fuel consumption for the Zaxis-3 machines compared to their predecessors, mainly thanks to the economical Isuzu engines and HIOS III.

All the daily checks on the Zaxis-3 range can be carried out from ground level, so there is no need to climb onto the excavators. Service and consumable replacement periods are also good – engine oil, and the engine oil and fuel filters have to be changed every 500 hours, while the hydraulic oil filter needs replacing after every 1000 hours. The hydraulic oil itself only needs changing every 5000 hours.

Features

As well as the rear-view camera, the Zaxis-3 range features an anti-reversing mechanism that makes slewing more precise and less jerky. Other worthwhile additions include an immobiliser that requires a four-digit PIN to be entered before the machines will start. This works alongside the GPS tracking/monitoring system to help deter theft. The GPS tracker can also be used to report back operating parameters like engine hours and operating temperatures.

Inside the low-noise cab there is a comfy &Ergo' seat with well-positioned joysticks that are shorter than on the previous models to help improve handling. A colour LCD display is fitted on the right-hand side to display operating information, or the view from the rear-facing camera.

According to Hitachi, many of the features of the Zaxis-3 range have come at the request of European customers. It is interesting to note that Japan's equivalent to the Tier 3/Stage IIIA laws don't come into force until October, which has helped drive this more Euro-centric agenda.

Mr Burger said, “Usually when Hitachi introduces a new machine, it does it in Japan and then it slowly moves out to the rest of the world. But for the first time, the new excavators had to be launched first in Europe.”