Fleet tracking has an unspoken boundary: the fleet you can track is the fleet with an alternator. Excavators, loaders, dumpers and trucks get a wired unit because there is power to take from. Breakers, buckets, grapples, compactors and shears get nothing, and carry on being managed by memory and phone calls. That is the wrong way round. Attachments are the things that go missing, that end up on the wrong site, that get worked far harder than anyone upstairs realizes, and that quietly consume the wear parts budget while the carrier they hang off sits in a report looking well behaved.
The reason is not that nobody thought of it. Wiring a unit into a machine is a job. It needs a technician, it needs the machine stood down, it needs a harness routed away from heat and pinch points, a fused supply, and a conversation with whoever owns the warranty. Multiply that across four brands and fifteen years of model changes and the rollout runs out of momentum somewhere around the third carrier, long before anyone gets to the yard where the attachments live. In any case an attachment has no supply to wire into, so the method does not reach it even in principle.
The Field Unit removes that whole category of work by bringing its own power. It runs on a sealed 28 Wh lithium cell inside a PA6 nylon housing molded around epoxy, with no seams and no service hatches. The housing is rated IP69K for high-pressure washdowns and dust. The specified operating temperature range is -30 °C to +85 °C. It measures 68 by 68 by 25 mm and weighs 170 g, which is small enough to sit on a flat face that most attachments already have somewhere out of the firing line. It fixes with screws to a maximum of 3 Nm, which is lower than most people's instinct with a driver in their hand. There is no wiring to the machine at all, not even a switched feed. It is made in Denmark.
What you take on instead is a budget. Battery life on a sealed device is quoted in transmissions rather than in years, because a figure in years would be a guess about your own settings dressed up as a specification: what SolidTrack quotes is typically around 4,000 transmissions at one transmission a day. The figure is a budget rather than a lifespan, and the part of it you control is how often you ask the unit to transmit. The practical consequence is that reporting frequency becomes an operational decision rather than a default you inherit. A breaker sitting in a yard for three weeks between hires does not need to report hourly. One out on hire, billed on usage, in an area where you have had thefts, probably does. The sensible approach is to set a frequency per class of asset rather than per unit, live with it for a season, and then adjust once you can see which assets you kept opening the map for and which you never looked at once.
Be equally clear about coverage, because this is where telematics marketing usually turns vague. The unit uses LTE-M with a 2G fallback and has no satellite link. Position may come from GPS/GNSS or mobile cellular positioning where available, but availability, accuracy and freshness depend on conditions, network coverage and reporting cadence. When there is no network, the store-and-forward log holds 300 entries by default and uploads retained records after connectivity returns. Longer offline periods can exceed available storage, so a stale last-seen time should be checked rather than assumed complete or treated automatically as a device fault.
Mounting is where a self-contained device is easiest to get wrong, precisely because it is so easy to fit. The Field Unit is rated for up to 8 g of shock and vibration, but it still belongs outside the direct impact zone. On a breaker, that means the carrier side or a protected face rather than a spot beside the tool that takes every blow. Do not bury it inside steel, because a metal box can obstruct both sky view and network reception. Where debris cannot be avoided, the protective cover seats the unit between two shock absorbers and uses four M8x50 screws on a 72 by 72 mm hole pattern to a maximum of 30 Nm.
Two administrative points are worth a paragraph because they are often where deployments stall. The SIM is embedded, so there is nothing to insert or swap. Hardware, connectivity and subscription scope are set out in the applicable quote or order. The second point is that a sealed device is a sealed device. There are no seams and no service hatches, which supports the IP69K rating and also means this is not something anyone opens in the workshop. Plan for units as an inventory item with a service life, in the same way you plan for anything else that is fitted and eventually replaced.
What all of this buys, in the end, is that an attachment becomes an asset with a record. Starter includes the Live Map, inventory, site boundaries, geofence breach, offline and out-of-hours alerts, utilization analysis, ideal strike rate, equipment documents and a monthly fleet report by email. Operations and Enterprise inherit those capabilities. For hydraulic breakers, impact-duration bands and telemetry-derived blank-firing indicators describe the hammer's recorded pattern, not the carrier that happened to be holding it that week. The everyday questions get easier at the same time: which site has the grapple, whether the spare breaker left the yard and when, or how much activity the compactor recorded during a hire.
If you are planning a rollout, the counter-intuitive advice is to start with the attachments rather than the carriers. The carriers are the machines you can already find, whose hours you already have, and whose absence you would notice by lunchtime. The attachments are the ones nobody can fully account for on a Friday afternoon, the ones that arrive back from hire in a condition nobody can explain, and the ones where fitting a unit takes a screwdriver and a torque wrench rather than a technician and a day of downtime. Start where the information is missing and where the fitting is easiest. It is not often that those are the same place.