Leveraging the power of PLCs

The T1 series PLCs that run the motors on the can printing machine are palm-sized controllers with CPU, I/O and power supply all in one block. The T1-16 measures just 122mm wide by 90mm high by 74.5mm deep.

Apart from the space savings, the PLCs have an instruction set suited to data transfer and arithmetic logic. Special functions are supported as well as basic ladder instructions. Processing speeds are dramatically improved over previous generation PLCs – from typically just under 100 micro seconds down to just 4.0 micro seconds for 16-bit transfer; and from 110 micro seconds down to 7.0 micro seconds for 16-bit addition.

Always a contentious issue with PLC users is the ease of programming. Toshiba has therefore ensured that the T1 range is totally compatible with the existing T Series peripheral tools. For ease of installation, the terminal block is removable on the T1 and there is a built-in computer link function via the RS232C port.

Because the operations are all controlled via the PLC and servo amplifier control boards, Retek’s machine brings time savings because the entire printing process can be reset by a practiced operator in about an hour – as opposed to an engineer spending possibly a whole day on the mechanical system. This is of particular benefit where the printing machines are required to do short runs.