I'm curious if anyone has details regarding the general purpose of function codes 13, 14, 40, 43.

My current understanding is as follows:
13: CANopen General Reference Request and Response
14: Read Device Indentification
40: Read/Write Object Dictionary
43: Encapsulated Interface Transport

Is there a documented usage of Function Codes 13 & 14 specific to Schneider applications that is different from above?

 

The descriptions you listed for 13 and 14 aren't Modbus function codes. Those are Modbus MEI "types" for use as parameters with function 43 (encapsulated interface transport). That is an important distinction to make. I don't however see 40 listed as an MEI object type. (Function 43 is normally used for tunneling CAN over Modbus/TCP).

It does say in the back of the "MODBUS Application Protocol Specification V1.1b" spec: "The following function codes and subcodes shall not be part of this published Specification and these function codes and subcodes are specifically reserved. The format is function code/subcode or just function code where all the subcodes (0-255) are reserved: 8/19; 8/21-65535, 9, 10, 13, 14, 41, 42, 90, 91, 125, 126 and 127".

So *functions* (not MEI type) 13 and 14 are not defined in the spec, but they are "reserved" (although nothing is said about 40). I suspect they are related to certain aspects of programming and management of Schneider PLC hardware. Exactly what they do probably depends upon the particular hardware being used (which is why they wouldn't be part of the communications protocol spec).