Datasheet for the 40MT160P, 122 KB PDF, catalogued here as a schematic. Devices with the MT designation in this series are power modules, commonly three-phase bridge rectifiers, and 160 usually reflects the voltage class. The document gives the internal circuit diagram, terminal numbering, outline and thermal data. A technician uses it to test each diode leg between terminals, confirm the module pinout against the board and choose a replacement with equivalent current and voltage ratings.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @cyberlanelectonik. Enginerys does not host this file.
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The standard format for schematics, block diagrams, power-sequence charts and service manuals.