The complete programmable controller standard applies to PROGRAMMABLE CONTROLLERS and their associated PERIPHERALS such as PROGRAMMING andDEBUGGING TOOLS (PADTs), TEST EQUIPMENT (TE) and MAN-MACHINE INTERFACES (MMIs), etc.This Technical Report refers to equipment for the control and command of machines and industrial processes used in OVERVOLTAGE CATEGORY II (IEC 60664), in low-voltage installations, where the rated mains supply voltage does not exceed 1 000 V a.c. (50 Hz/60 Hz), or 1 500 V d.c.PROGRAMMABLE CONTROLLERS and associated PERIPHERALS (PC system) are considered COMPONENTS of a control system and may be provided as ENCLOSED or OPEN EQUIPMENT. This report deals with the PC and interfaces to the other parts of the AUTOMATED SYSTEM and does not deal with the whole automated system itself (see figure 1a).