Speaking as someone with direct access to the inner workings of the pump standard ... now, consider the following comments to be absolute Gospel from the ultimate authority- if presented in a casual manner:
The pump standard has all manner of provisions regarding pumps and the use of cords with them. There has been some 'loosening' of the rules in the past few years as various matters have been clarified.
Simply put: Lighten up, people! Just about any pump can be fitted with any cord, of any (reasonable) length, and not violate the listing & labeling. Even rigging a cord to a pump that is "usually" hard-wired does NOT constitute a violation of the listing.
The connection boxes are evaluated using the biggest connectors that will fit. Various pump makers have provided plenty of substantiation for the use of cords in various situations. There's a whole industry (IE: Meltric) built on the idea of using cords.
True, the details CAN matter. For example, it is imagined that a pump in a wash-down situation would be connected using wet-location fittings. It's the responsibility of the AHJ, and not the testing lab, to judge whether a particular fitting and cord are acceptable.
Yes, there has been a lot of parsing with regards to dishwashers and disposals. Those are different appliances, and are evaluated under a different standard than the one for electrically powered water pumps. Different standards, different committees, different rules. (Witness the recent increase in the allowed length of cord on a dishwasher!).
The OP asked about pumps in an industrial environment. This introduces several "special exemptions" into the question. These include vibration isolation, ease of maintenance, and a 'supervised' maintenance program with 'qualified' people.
Now... that said ... there are a heck of a lot of pumps that are not 'listed' by anyone. The pump industry has a century-long history of producing all manner of top-quality, perfectly safe pumps without the blessings of any testing lab. You can't violate the listing of something that's not listed!
