LIFTKET works mainly in three product divisions - Industry, Custom and Stage. For these, the corresponding products are adapted to specific requirements. LIFTKET's innovative spirit is reflected in the latest development in the hoist sector. Jnrgen Dlugi, CEO, talks about the new product in the market - the STAR VFD.

What was the motive behind the development of your new STAR series?
There was a gap in the LIFTKET portfolio. We did not have that particular premium chain hoist, I mean a fully equipped chain hoist with a modern control that allows a soft start, load dependent lifting speed, variable lifting speeds and, for example, brake monitoring or the observation of operation states. Our goal was a tailor-made plug-and-play solution for the popular STAR LIFTKET series with no external brake resistance and the opportunity to increase the lifting speed up to 200 per cent with no load. Furthermore, the aim was not to modify the STAR LIFTKET's basic design so that the VFDs are fully compatible with all standard LIFTKET components such as trolleys, upper hooks, suspension eyes, and control pendants.

The STAR VFD is your first frequency-controlled electric chain hoist. Why did you decide to develop this type of product?
In fact, the VFD is not our first frequency controlled chain hoist. We used to have chain hoists with external inverter controls before, but in our opinion, it was time to fathom the limits of the machinery and to invent something new. The benefits for the customers are better comfort of use, an enormous time saving and even more simple maintenance.

What are the advantages of that frequency-control?
The main advantage beside time savings during lifting with no or partial load and to have the opportunity to pick up and set down fragile goods very carefully is the Quick Stop function that makes the chain hoist to stop immediately with no overrun after releasing the up/down button completely. The Quick Stop ensures the highest safety and helps preventing accidents or dangerous situations.

We use the standard two-stage control pendants which our customers already know from the contactor controlled chain hoists. The operator can choose between two different operation modes to make the chain hoist work properly, according to what the user wants and/or to what the application requires. We call these modes Reduce Speed mode and Hold Speed mode.

In the Hold Speed mode, the chain hoist keeps hold of the momentary lifting speed. In this mode, it is possible to have a constant lifting speed that is somewhere between the highest possible and minimum speed.

In the Reduce Speed mode, the lifting speed decreases along a certain ramp down to the minimum frequency of 5 Hz when the operator releases the button to go back to the first stage. This gives you a quasi analog feeling but with the affordable price of a basic two-stage pendant.

Of course, control pendants with analog push buttons which work like a gas pedal are available on top of the range.

What is the purpose of integrated display in STAR VFD?
The display shows different data such as remaining life time, operational hours or brake cycles in a repeating order. This saves the technicians the time for the calculation of the safe working period and gives a chance to monitor the operation frequency or rather the number of starts per hour. Beyond that, the display shows error codes once the chain hoist stops, in case of critical operating states. With a translation table in the manual, the operator can easily reset the chain hoist or can at least get information regarding the reason for the stoppage, which simplifies the troubleshooting.

(Communication provided by company)