I work in the live entertainment biz where PowerCON connectors are super common, there are two different PowerCON connectors, the 20 A and the True1, there are few small differences between them. The 20 A is rated for 20 amps and is traditionally blue. The True1 is rated for 16 amps and is traditionally yellow. The True1 also makes the ground contact first, the 20 A doesn't.
Using them on your power tools is a brilliant use for them! Since you have yellow connectors, are you sure you have the 20 A and not the True1 connectors?