The transmission of analogue signals may involve the inclusion of some errors when measurements are transmitted to other appliances, for example. For this reason, we have supplemented our range with equipment using digital transmission formats. This method enables the connection of large-size meters that can display identical values as those fitted to a control unit. The software developed for these RS-type meters enables their use as general-purpose meters for any digital quantities (including mnemonic messages). Such meters, when combined into complex networks using the ModBus system, can display information transmitted from the master PC of the PLC controller.