Lenze Drives Take The Biscuit
Repeated drive failures at a biscuit factory in Yorkshire, UK, caused major problems, including lost production. The original IP20 drives used at the factory were suffering from contamination, which was causing them to fail prematurely.
The original IP20 inverters (typically rated 0.75kW), were driving conveyors on biscuit production lines at the Yorkshire factory. Any stoppage of the lines meant lost production - but, unfortunately stoppages were many - and costly, due to the resulting downtime and the cost of replacing the failed inverters themselves. Replacements were readily available from a catalogue retailer - however, these drives also failed - probably because, they too, were IP20 units and susceptible to the same operational problems as the original inverters.
At this stage, engineers from Lenze's local solution provider, was called in to investigate the unexplained failures. They concluded that the inverters were suffering from severe infiltration of dust, which was causing them to overheat and then fail prematurely.
The solution proposed by Lenze was to replace the IP20 drives with IP65 Enclosed SMVector Inverters from Lenze. The retrofit of these drives offered a number of advantages.
First, SMVector drives are designed for mounting without a panel or cabinet, their standard IP65 rated enclosure providing protection from dust, dirt, debris, water jets, food products and diluted cleaning products.
Second, the IP65 rating meant that the biscuit manufacturer did not have to invest in control cabinets, which were both costly to buy and install, and would have increased the footprint of the conveyor control system.
Third, the fact that no cabinet was required means that the drives could be positioned closer to the motors they are driving. This reduces both wiring and installation time. It also means that equipment is easier to move and reconfigure in today's flexible production environments.
Fourth, the SMV inverters solved a problem where some operators would make unwanted changes to the settings of the drive. The SMV has password protection_ this means that operators have access to the integrated display and keyboard, but cannot change the parameters of the drive without knowing the password.
Fifth and final, the SMV features a Programmable EPM Chip, which allows users to copy across in a matter of seconds an entire operating set of parameters to another SMV drive.
In pressurised operating environments such as food production a replacement EPM chip can often be used to return a machine to service without having to call out a support engineer, or commit skilled programming time to recommission an individual drive.