Ling
Systems Ltd have recently completed the installation for the Line 1 Air Conveyor
system at Coca-Cola Enterprises Ltd, Edmonton. The handling system supplies
empty PET bottles to a rinser/filler/capper bloc from either a de-palletiser,
a Sidel blowmoulder or a Krupp blowmoulder, with a combined output of over
31,000 bottles per hour. The total conveyor line covers over 2000 metres and
incorporates to 2:1 gate units and as well as bend, incline and decline sections,
it is powered by 29 2.2kw silenced fans. The handling system was supplied
with full PLC control as follows:
The extent of the bottle flow i.e. any backlog or gaps, is monitored by PECs along the line. These feed back info to the PLC and affect fan speed and directional switching of the 2:1 pneumatic gates. The fan motors are controlled by Danfoss inverters, which are linked to the Allen Bradley PLC over three Profibus networks via conversion units to translate signals. These allow four fan speed settings; Low, Medium, High and Boost. The system includes two Allen Bradley PanelView touch screens, one at the filler end of the line, the other next to the blowmoulders. These control the set-up parameters of the PECs and PanelView stations communicate with the PLC via a DeviceNet network. On-site wiring along the 200 metre + length was carried out using trunking and accessories from Electrix International.
The
air-conditioned panels also controls the pneumatic ‘Auto-brush’ side guides
on the conveyor, which can auto adjust for a variety of 0.5 litre (inc. Coke
contour, Sprite and Fanta) or 2.0 litre bottles. Pressure switches along the
conveyor warn the operator when the4 air filters for each fan need changing
by setting off a warning light. Motor isolators, remote and emergency stop
buttons are provided, and the system provides volt free interface signals
to control the operation of the blowmoulding machines. For example, to halt
the supply of bottles when the filler stops. The completed system operates
well above the target 85% efficiency.
