APPLICATION BULLETIN - MARCH 1995 | BACK TO INDEX  

PDL motor controllers pass the Cedenco quality test

Gisborne-based Cedenco Foods Ltd are among New Zealand's leading processors in the specialised food ingredient field and recently passed another milestone in their history with the commissioning of turn-key Rossi & Catelli tomato paste and particulate production lines. Fuelling this growth is an increasing world demand for prepared sauces and Italian-based food products - all those pizza, pasta sauce and salsa ingredients which are such a common feature of modern consumer dining.

Cedenco's state-of-the-art plant produces a range of aseptic purees and dried products based on tomato, sweetcorn, squash, apple, kiwifruit and other locally grown produce for a group of customers which include some of the biggest international brand names in the processed foods business - Maggi, Uncle Ben, Campbells, Watties, McCoy and Dolmio.

With a processing potential of one hundred tonnes of raw product per hour, 24 hours a day on a continuous shift basis, this modern Italian-sourced plant places some demanding conditions on both process machinery and the technical staff who supervise its operation. In the circumstances it's perhaps not surprising to discover that behind all this leading edge international processing technology lies some equally advanced equipment bearing a well known New Zealand trade name - PDL Electronics.

Says Cedenco site engineer Arie Veenstra "Over the years since I helped establish the plant we've installed practically every type of drive PDL produce - the old Autotronics, ASDs, Picodrives, Microdrives - we've got the lot. The original PDL drives we bought ten years ago are still working. All the motor drive controllers on our pumps, conveyor motors, driers and so on come from PDL and when we asked Rossi & Catelli to design a new plant for us we specified PDL controllers for all the drive functions."

"Actually I designed the whole electrical layout of the new plant with PDL drives in mind. I've had ten years experience of PDL and its gear and could back up what I had to say about its performance when the subject of what drives to fit came up with the Rossi people. So they built in their part of the control system to our specifications and when the plant modules were delivered to Gisborne all we had to do was wire in the drives."

"PDL produce a very reliable product and I've never had a downtime problem with their equipment despite the fact that at times its being pushed to its limit. An important factor for us is that Napier is our neighbour and PDL's backup service is literally just round the corner."

"You have to remember," explains Arie, "that tomatoes are 95% water. So to finally arrive at a suitable paste concentrate you are going to have to remove a large volume of water."

PDL controlled conveyors move the whole tomatoes from the delivery point through four holding pools capable of floating 150 tonnes each of produce, up an elevator to an electronic colour sorting station. The product then goes to an El Dorado hot break system which deactivates the enzymes in the tomato pulp. After removal of seeds and skins the final pulp is then concentrated in a huge four stage, three effect, continuous evaporator working under vacuum and is then pumped through a steriliser and packed aseptically into 250kg and 1000kg drums. At this final packing stage the product is the familiar tomato paste that embellishes the family pizza and other Italianate goodies. "It takes six tonnes of tomatoes to get one tonne of paste and with this new plant we can get fourteen tonnes of product per hour. Our previous plant could only produce five tonnes an hour which gives some idea of how much we've increased our capacity."

"All the pumps, conveyors and elevators are on motor controllers purely for mechanical and processing reasons." says Arie. "We need the soft starting capability of the controllers so there is no mechanical strain on the drive trains and we need the speed control capability so we can handle the varying through-put demand. The added bonus is a cost benefit from the energy savings you get with both features."

"From my experience with the PDL controller I've come to the conclusion that the AC motor drive has an absolutely essential role to play in modern process engineering. They have become so sophisticated in the things they can do that as an engineer you are always learning new ways you can use them."

PDL Electronics general manager David O'Donoghue us pleased with the success of the new Cedenco installation and its endorsement of PDL quality.

"Rossi & Catelli are extremely sensitive about their international image and won't touch anything unless it comes up to their standards. Apparently when they put in a plant recently in Russia they shipped in absolutely everything down to food, wine and medical staff so that they could complete the contract to their high standards. Their acceptance of PDL's motor control technology underlines that our ISO9001 quality standards meet the best specifications anywhere in the world."