How we modernised multi-zone refrigerated transport with a modular system
This programme reflects TAD’s core approach: collaborative scoping, operator-first design, and engineering that balances performance with serviceability. By owning electronics, firmware, HMI and integration, we removed friction between disciplines and delivered a practical upgrade with real-world impact – modern controls that simplify life for operators while protecting cargo and reducing maintenance burden.
If you operate complex, multi-zone systems – on the road or on site – and need a clearer, more reliable control strategy, we can help. Talk to us about modular controls, remote interfaces and vehicle integration that make operations simpler, safer and more efficient.
Hultsteins – leaders in sustainable, energy-efficient transport refrigeration – needed to upgrade the controls on their multi-zone systems. The incumbent platform had become expensive to maintain and overly complex, putting product integrity at risk through potential temperature drift and unnecessary downtime. The brief was clear: deliver a modern, modular control system that maintains precise temperatures across zones, simplifies maintenance, reduces wiring complexity, and integrates cleanly with the vehicle environment.
We designed a control architecture built around replaceable modules and a small, intuitive Human-Machine Interface (HMI). The modular design means critical functions can be swapped quickly, minimising disruption and cost. The HMI foregrounds clarity: symbolic buttons reduce reliance on text, lowering training overheads and making the system instantly usable across international fleets.
To support real operations, we embedded a Wi-Fi access point on the unit. Any authorised device with a browser can connect to a simple web UI to monitor status or adjust parameters – no special software required. This enables faster commissioning, fewer call-outs, and better oversight for distributed fleets.
We engineered custom PCBs and enclosure hardware to manage clutches, solenoids, and pressure sensors reliably, within a compact footprint that’s easy to service. Close attention to layout and service access keeps wiring to a minimum and accelerates routine maintenance.
Using our experience with control systems and CAN communications, we integrated to the vehicle’s CAN Bus, exposing richer operational data and optimisation. This tightens the loop between refrigeration performance and vehicle behaviour, supporting more efficient operations.
Throughout development, we focused on day-to-day usability and long-term reliability: simple interaction for drivers and depot staff; clear service paths for technicians; and a control strategy tuned for temperature stability with efficient energy use.
Hultsteins needed precise multi-zone temperature control without the wiring complexity, fragility and cost of their legacy platform. The incumbent system was difficult to service, lacked remote access for configuration and diagnostics, and created training overheads across multilingual fleets. Any upgrade had to minimise downtime, integrate cleanly with vehicle CAN bus, reduce operator error via a simpler HMI, and improve energy efficiency – without compromising food safety or adding maintenance burden.
The new system delivers what Hultsteins required: precise temperature control across multiple zones, easier servicing, improved reliability, and lower operational friction. With remote configuration via the onboard Wi-Fi interface, teams can make changes quickly and verify behaviour from any browser, reducing dependence on specialist tools. Symbol-led HMI design translates effortlessly across languages, improving user confidence and reducing training time. And under the hood, CAN Bus integration and robust PCB control of clutches, solenoids and pressure sensors provide a dependable platform that scales across vehicle variants.
Operationally, the combination of modular hardware and streamlined wiring reduces time off the road for maintenance, while the simplified interface cuts routine errors. These practical gains support energy-efficient running and help safeguard temperature-sensitive cargo – key outcomes for any refrigerated fleet.