20 years of Zapfi production: Interview with Ing. Herbert Kastner

PTO units are emergency generators that are driven by the tractor. Today, MOLL-MOTOR is one of the best-known manufacturers in Austria; the start of serial production took place exactly 20 years ago. On the occasion of this anniversary, we talk to Ing. Herbert Kastner.

Since 1996 sales representative at MOLL-MOTOR, he advises companies, municipalities and private customers on our entire product range. At the same time, Ing. Herbert Kastner is a specialist for the product group generators and in this role he is significantly involved in the further development of our latest Zapfi series “ZGN”.

Mechatronic drive technology is a broad field, power take-off units a small niche. Why did the company decide to offer exactly this product?

Ing. Herbert Kastner: There has always been a need for emergency power units. Especially for dairy farms, which are often single farms on higher ground. There, they have completely different snow conditions and wind peaks, and therefore power outages can occur more frequently. Using the tractor as a power source is simply the best solution, because there is no need to maintain the additional combustion engine of a generator. In the beginning, we met the demand with purchased products and quickly realized that we could improve many things about them.

Then, 20 years ago, MOLL-MOTOR ventured into series production, and you were there. What can you tell us about the challenges in 2003?

Ing. Herbert Kastner: We didn’t have a 3D drawing program and it was an insane amount of work to do everything in AutoCAD. A former colleague, a mechanical engineer, drew the first frame. When you design a machine, you also have to consider the production steps, otherwise the assembly will be a fiddly job later on. And the suppliers for gearboxes, measuring instruments, etc. must be fixed and reliable; problems often lie in the details. When the finished product is ready, everyone thinks: “It’s all logical anyway,” but the effort involved should not be underestimated.

How did the customers responded to this first series?

Ing. Herbert Kastner at the Agraria 2004 trade show in Wels, Upper Austria

Ing. Herbert Kastner: We went to trade shows and promoted the aggregates. At the beginning, the price was an issue, but then the units were compared on the market. There were some without insulation monitoring that needed an earth spike, which was then much too short. Once customers realize what they can do to themselves with a bad device, and that our product is well thought out and offers safety, the price is no longer the main issue. After the first hundred units had been sold, word of mouth came into effect. Then you heard, “Someone in my town is very happy with it, I want one like that, too.”

The new ZGN series has been available since 2021. What are the improvements and where do they come from?

Ing. Herbert Kastner: After thousands of sales talks with customers, you know what matters. One tells of his milking robot with a sensitive control system and what voltage quality it needs. Another raises the question of what happens in the house when a large light current consumer comes on that is on an unmonitored phase. Electrotechnically, my retired colleague Erich Schiessling was instrumental in the new series; he read up intensively on the standards, clarified everything and found suitable solutions for all conceivable problems. In the ZGN series, we rely 100% on 3-phase actual value acquisition. In addition, the MeccAlte generator we use is certainly the highest quality on the market in terms of control behavior. And customers also find our operating manual understandable and are happy to have it available on the homepage.

Mechanically, there have been some changes, also on the suggestion of customers?

Ing. Herbert Kastner: The new, higher lower link angles, for example, came from me. This was our reaction to the fact that there are more and more large tractors. The additional holes on the ZGN-32 are also for users with large tractors; they can move the generator on the frame to the rear. We have reinforced the frame itself and had the design thermally calculated so that nothing bends under greater forces. There is a stable wheel set so that none of the wheels break off if the unit is set down at an angle. And the wheels are dimensionally stable, even if the unit stands on a shelf for years. We have had the sturdy control box for a long time, and customers appreciate it.

Is the production of the PTO units 100% at the location in Stockerau?

Ing. Herbert Kastner: Correct, we mount generators and gearboxes on the frame, build the control cabinets ourselves, assemble the cable harnesses, and much more. There have been attempts to have simple things manufactured externally. At the beginning you get an interesting price, but with each order there is an increase. I am glad that we have all the manufacturing steps in-house. There is a stable company behind it. Because MOLL-MOTOR has 100 employees, someone from another department can help out when there’s a need.

Finally, can you tell us what the next steps will be?

Ing. Herbert Kastner: Now that we have the supply situation of the material under control again, we have to shorten the delivery time for the customers. We still receive an enormous number of orders because many customers are ready to wait several months for reasonable quality. And because those aggregates that are quickly available on the market often don’t even meet the standard and are unsafe. But we can’t keep customers waiting too long. Besides, we keep our eyes open when there are technical innovations in agriculture, then we can adapt the PTO unit again.

Technical information about this product is summarized on the following page: Power take-off generator ZGN – MOLL-MOTOR

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