Problem Solving (Yes - also under reconstruction...)
We worked with the first generation of Thyristor Drives (at ABB/ASEA and Siemens) in the Sixties. We worked with the first Variable Frequency Drives in the Seventies.
We have done most of the mistakes one can do - and we have also seen some that others did. That has given us a broad and deep understanding for all kinds of problems and interference - how they are born, how they breed and how they attack all sorts of equipment. We have learned how to catch those elusive creatures and also how to kill them in an effective and "human" way that does not affect other equipment.
How does that help you? In many ways. Would you rather hire someone that is as bafflled as you - or someone that probably has seen the same kind of problem many times before? Someone that knows how to identify, quantify, rectify and verify the problem and its solution or someone that barely understands that there is a problem at all?
We surely know what guy we would hire if we were having problems.
Big words - yes. And there are resons for that. In one of our latest assignements, five attempts had been made to solve a problem with large variable speed drives that failed very frequently and eventually had to be shut down until a solution was found. The drive supplier (USA) made two attempts to solve the problem and then, there were three more (one Asian and two African) companies involved without any success. GKE found out what the problem was in a little more than a week. There were two problems, actually, and that may have obscured the view for those who tried before us. A "de-identified" report is available on request. Mail firstname.lastname@example.org or phone +46 70 651 07 84 for a copy.
There are also problems that you may not be aware of:
That is quite common in paper-making and other high-speed continuous processes. Speed variations that go undetected because of SCADA low sampling rate, slippage, alignment problems, instability, temperature drift, hardness control and web tension problems in winders and many other "yield eaters" that reduce production by from one to, perhaps, five percent. For a typical mid-sized paper machine (producing at 4000 €/hour) that would cost you between 300 000 and 1 500 000 € each year.
A thorough "Health Check" costs between 1000 and 2000 € for each section in a machine - a small cost for a 300 000 to 1 500 000 € gain. And, if nothing special is found, it is still a low cost for knowing that stability, transducers, set-points, couplings, web tension, alignment and everything else is OK in the drives.