Spanning 1SMA10CAT3 to 78CAT3 according to its name, this 81.5 KB PDF is filed as a schematic but describes a component range, the CA suffix typically marking bidirectional transient voltage suppressor diodes in SMA packages. No device or board number is stated. Use it to find stand-off and clamping voltages for a marked TVS part, especially when a protection diode on an input line has shorted. Opens in any PDF reader. Pick a replacement with the same voltage rating and direction.
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.