Drives help breathe new life into old machines

Edited by the Engineeringtalk editorial team Aug 5, 2005

Bradford based industrial electric engineering specialist Appleby is using 7.5kW smd drives as part of a complete electrical refit for older models of Heidelberg embossing and cutting machines.

Bradford based industrial electric engineering specialist Appleby is using 7.5kW smd drives as part of a complete electrical refit for older models of Heidelberg embossing and cutting machines.

The drives have made the refit possible due to their compact sise and high power handling capacity.

Other user-focused features such as the innovative EPM chip have provided Appleby with fast programming and low cost service support.

The package from Lenze also includes a dynamic braking option to control high inertia loads.

The Appleby electrical refurbishment package for Heidelberg printing and finishing machines includes a complete rewire and replacement of the old slip-ring electric motors.

The package uses a PLC based control system, a Lenze smd drive and a touch screen HMI.

Martin West of Appleby explains: "The control panel is fitted into a cabinet on the machine that was originally designed for storing tools and maintenance spares, so the space available for the drive is severely limited".

"The Lenze unit is ideal because it is very compact; around half the size of some competitors drives we considered".

"Drive programming is also flexible without being too complicated so commissioning is far simpler than with other drives we have encountered".

Finishing machines bring an added challenge because the drums tend to be very heavy.

The spinning mass of the drums allows the machine to cut and emboss card and heavier weight paper in a smooth process, but this creates a fast cyclic load and unload sequence for the drive to manage.

The added torque required to start the press rolling, and then control the speed of the drums when they are spinning demands a high power handling capacity from the drive.

The high peak load handling of the smd drive takes care of the drums inertia when accelerating.

A smd specific dynamic braking kit is used to reduce speed, working with the drive to inject braking current into the motor and provide the fine speed control needed to ensure the print registration is kept within extremely tight tolerances.

"The EPM programming chip has also made a great difference to the servicing support aspect of our work", explains West.

"If the drive were to be damaged and need replacement or the programme parameters are changed and need to be returned to the original setup, then we simply copy a chip which is kept in the job file and supply it to the end user straight away".

Copying the original operating parameters onto a new chip, which is embedded into a tough 10mm2 protective plastic cover, takes only 3s using the desktop EPM programmer.

A blank chip is plugged into the facia and the programming copied across from the onboard memory or a master chip at the press of a button.

The mechanical side of the rebuilds and overall project management is completed by specialist print machinery refurbishing company Selective Printing Machines, also based in Bradford.

The finished printing machines are transformed from a mainly manual, to a fully automated, programmable printing press with preset operating programmes and touch screen controls.

The mechanical build quality of the old machines ensures that first class results are possible from relatively old donor machines, but printing speeds and hence overall productivity are increased dramatically.

Fine control over print speed and registration is also made simple using the new automated controls that can trim and change a range of parameters from one touch pad.

The smd range is available in power ratings from 0.25 to 22kW and an input voltage range from 200 to 480V in both single and three phases in order to cater for domestic and industrial applications, and export sales.

The EPM memory chip is a standard feature on all models; the dynamic braking kit is part of a wide range of optional accessories including remote keypad control, through hole mounting for the heatsink and many more.

Lenze smd drives are supported internationally by AC Technology International.