How to choose an excavator (and what size you need)

1. Start from the job you repeat most

Buying for the exception leaves you with an expensive, slow machine the rest of the year; the exception is what you rent for. The everyday job defines the class. For reference, the catalog runs from 1.2 to 118 tonnes (figures from Bobcat and Komatsu datasheets):

• Micro and mini (1–6 t): trenches, indoor work, landscaping and urban jobs. The Bobcat E10 weighs 1,176 kg and at 710 mm wide fits through a standard door; the E26 (2,625 kg) still travels on a trailer behind a pickup.
• Large compact (6–12 t): the Bobcat E80 (8,260 kg, 4,600 mm digging depth) tops the compact line; the Komatsu PC130-8 (11.7 t, 0.5 m³ bucket) fits urban streets and farm roads.
• 20 t class: earthmoving, truck loading, foundations and road work. The PC200-10M0 weighs 20.3 t and carries a 1.0 m³ bucket.
• 30–50 t class: continuous production and quarrying. PC300-8M2 (31.6 t, 1.96 m³), the rock-reinforced PC360-8M2 and the PC500LC-10M0 (49.4 t, 3.2 m³).
• Mining (58–118 t): PC600-8, PC800-8 and PC1250-11R, chosen as part of a loading and hauling fleet.

2. Depth and reach: compare them with your drawings

With the rough class set, go to the figure that decides: maximum digging depth against the deepest trench or foundation on your drawing. That number belongs to a specific arm configuration — the Bobcat E55z, for example, goes from 3,434 to 3,834 mm with a long arm —; if your design sits close to the limit, go up a step or ask for a long arm.

A long arm gains reach but loses breakout force: for rock or demolition, prioritize force. When the datasheet lists forces measured under ISO 6015 — the PC300-8M2 states 171 kN at the arm and 228 kN at the bucket, per Komatsu — compare brands on that same standard.

3. Tracked or wheeled excavator: which one suits you

Tracks: they spread the weight, do not sink in soft ground, climb slopes with more traction and are more stable when lifting to the side. They are the choice for earthmoving, uneven ground and fixed sites; changing fronts means hauling them on a lowboy. Wheels: they drive themselves on the street, do not damage asphalt and set up fast, but need outriggers or a blade to dig firmly and do worse in mud.

Rule of thumb: if the machine spends more time traveling on the street than digging, wheels; if the ground is soft or the site is fixed, tracks. In the catalog, every Komatsu excavator is tracked; the wheeled option is the Bobcat E55W mini excavator (5,550 kg, 3,495 mm digging depth and 30 km/h travel speed, per Bobcat), in El Salvador and Panama.

4. Working space and transport

On urban sites, against a wall or next to traffic, tail swing matters as much as size. Zero-swing mini excavators — the Bobcat E20 and the z series (E35z, E50z, E55z) — rotate without the counterweight leaving the track width: you dig next to the wall without hitting it. The E20 also has a retractable undercarriage: it narrows to get in and widens to work stable.

Also count how you will move the machine. A 2–3 t unit travels on a trailer; from the 12 t class up you need a lowboy, and that freight is paid on every change of front.

5. Power and cycle: same class, different machines

Within a class, the difference is in the cycle. The PC200-10M0 and PC210-10M0 carry the same 1.0 m³ bucket, but the PC210 has 165 HP against 138: where the cycle is short and repetitive — hopper, quarry, pads — it fills faster; on sites with a variable pace, the PC200 performs the same and burns less.

The same happens higher up. The PC300-8M2 and PC360-8M2 are both 30 t class, but the PC360 carries rock-reinforced work equipment. If you move soil, the PC300 does the job for less; in rock, the structure suffers more than the engine, and that is where the reinforcement pays.

6. Attachments and auxiliary hydraulics

With a quick coupler, the same excavator breaks with a hammer, demolishes with a shear and trims with a grading bucket. Check auxiliary flow: the Bobcat E50z delivers 75.7 L/min, which per its datasheet lets it run a hammer all shift. Komatsu offers more than 50 hydraulic hammer models, each specified by the weight range of the carrier excavator.

Order the hydraulic line from the factory: retrofitting costs more. And choose the bucket by the material, not by volume; we cover it in the bucket guide.

7. The operator and monitoring change output

The same machine performs differently depending on who runs it: a trained operator burns less fuel, looks after the undercarriage and works safely. The group's APMT Academy runs a basic excavator course.

With Komatsu, KOMTRAX comes included at no cost to the customer, per Komatsu: location, real hours, fuel use, idling and maintenance alerts from a computer or phone. With that data you know whether the machine is sized right or spends half the shift idling.

8. Where to buy or rent, and who backs you

A stopped excavator does not cost the part: it costs the workday. Before the brand, check who has parts and a workshop in your country.

Grupo ConstruMarket is an authorized Komatsu dealer in El Salvador (Zaragoza, Antiguo Cuscatlán, San Miguel), Guatemala as CMARKET (Mixco, Río Hondo, Xela), Nicaragua (Managua) and Panama (Panama City), with its own workshop and service in the shop or on site. Komatsu Warranty Pro extends coverage up to 60 months or 12,000 hours, per Komatsu. Bobcat mini excavators are sold in El Salvador and Panama.

If the job is short, RentaCentro, a group company, rents excavators: its fleet includes the Komatsu PC200 and the Bobcat E50z (confirm availability in your country). There are also inspected used machines, sold as is, and financing through credit or leasing subject to approval.