Multi-level sample transport, Brisbane pathology lab.

5 levels. 18,000 samples a day. Every tote addressed.

This was a greenfield pathology facility at Bowen Hills, Brisbane. The conveyor system spans five working levels, moving tote bins between collection, processing and storage areas throughout the building. Pac Technologies was engaged to write all PLC and motion code for the transport layer.

The control backbone is an Omron NX PLC communicating over EtherCAT. Two servo-driven lifts carry totes between floors. Thirteen ZEN-controlled transfer units handle routing across each level. Every tote carries an RFID tag, so the system knows each container's destination from the moment it enters the network.

Industry

Healthcare — Pathology

Service

Programming

Location

Bowen Hills, QLD

Year

2016

Control

Omron NX PLC · EtherCAT

Identification

RFID container addressing

Chain of custody, five floors, no margin for error.

Pathology samples carry strict chain-of-custody requirements. Every tote must arrive at the correct floor, correctly identified, without gaps in traceability. A misdirected or untracked sample is not just an operational problem: it has direct consequences for patient care. The system needed addressing that was positive and container-level, not inferred from position.

The Bowen Hills building footprint made a vertical layout the only viable option, which meant two lifts sharing a physical space. They had to coordinate precisely to avoid collision and queuing delays. Per-level safety zoning was also a firm requirement: maintenance or an incident on one floor could not be allowed to halt the rest of the building. The system had to keep running on all unaffected levels while a single zone was isolated.

EtherCAT backbone, RFID at the tote, safety zones per level.

Omron NX over EtherCAT was chosen for its real-time determinism. Coordinating two servo-driven lifts in a shared shaft requires cycle-accurate synchronisation: EtherCAT's fixed bus cycle removes the timing uncertainty that can accumulate over a standard industrial Ethernet network. Both lifts report position and status on every cycle, and the motion logic arbitrates access to each floor without depending on timeouts or polling.

RFID at the tote level means each container carries its own routing identity. The system reads the tag when a tote enters the network and again at each transfer point. There is no positional inference, no reliance on counting or sequencing to know which sample is where. The thirteen ZEN-controlled transfer units each hold their own routing logic locally, so the central NX is not the decision-maker for every divert. That distribution reduces the load on the main PLC and keeps individual transfer units responsive even under high throughput. Per-level safety zoning is implemented as discrete safety circuits: isolating a floor for maintenance does not require a system-wide stop, and the remaining levels continue to run.

PLC

Omron NX

Backbone

EtherCAT

Lifts

Two servo-driven

Transfer units

13 ZEN-controlled

Identification

RFID at tote level

Safety

Per-level zones

18,000 samples a day, addressed and delivered.

The system has been in production since 2016, moving 18,000 pathology samples per day across five levels. RFID addressing at the tote level maintains destination accuracy regardless of throughput. Per-level safety zoning means the facility can run planned maintenance on a single floor without stopping the rest of the building.

• 18,000 tote movements per day across five levels
• Positive RFID addressing at container level throughout the network
• Per-level safety zones allow single-floor isolation without system shutdown
• In continuous production since 2016