IP67 PLC controls Transport Modules in Coldstore

Asbreuk Service B.V. equipped a Dutch logistics supplier with a fully automated and modular loading and unloading system for trucks – with the decentralized control at ambient temperatures of -25 °C provided by Turck's rugged TBEN-L-PLC IP67 modules

Robust PLC reduces cabling

Their ability to be used in cold storage warehouses at ambient temperatures of -25 °C was what attracted the Dutch family owned company to Turck's IP67 TBEN-L-PLCs. “For us it was important for the controller to have the ability to communicate with different bus systems and at least operate at temperatures as low as -30 °C,” says managing director Marco Asbreuk. “There is actually only one PLC suitable for this field, and so the decision to use Turck's TBEN-L-PLC was more or less obvious from the start.” The decentralized modules also require considerably less cabling; According to Asbreuk, this enables an “enormous saving in costs, particularly in the coldstore area, which requires the use of special cables.”

Autonomous conveyor system with pallet check

In the factory of the French fries manufacturer, Asbreuk Service provided each of the 32 line modules with their own controller. These modules include chain and roller conveyors as well as a section for inspecting pallets. Laser sensors here check whether a pallet is too wide – and is therefore incorrectly packed. Lasers and scanners are connected locally to the relevant Turck PLC. Only an identical TBEN-L-PLC module, which acts as a higher-level central controller and is connected via a CAN bus, is used for removing pallets.

Expansion via ultra compact TBEN-S-2COM

A conveyor element with three directions is required to transfer individual pallets from the usual line route to the buffer. As each direction requires a separate RS485 port, one Turck I/O module provides the additional range of interfaces at this node. The ultra compact TBEN-S-2COM I/O module connects the serial interfaces directly in the field to the controller via Profinet so that the RS485 functionality is retained.

If a coworker nevertheless has to intervene in an ongoing process, this person can control line sections individually at two modular and decentralized operator panels. Functions such as a controlled stop or the running of an alternative route are possible. 

Multiprotocol modules in the control cabinet

Signal transmitters such as pushbutton actuators at the control consoles require additional inputs and outputs. The Dutch engineers therefore installed three IP20 I/O devices in the cabinets: Turck's FEN20-16DXP multiprotocol modules effectively make standard switching signals bus-capable in a short time. However, the use of the FEN20 modules is not only restricted to the control consoles: Central control is still retained in the automatic truck loading system (ATL), which the pallets reach by means of a hydraulic lift. The area is monitored by a centrally controlled frequency converter and a Siemens PLC. Turck's FEN20 offers additional inputs and outputs in the control cabinet and communicates with the main controller. However, Asbreuk is not excluding the possibility of soon implementing the decentralized operation of an ATL zone.