In previous posts like this I discuss the importance of handcrafting claim language, down to carefully picking verbs and nouns that clinch the spirit of the invention while reserving the maximum territory of the art.
An important difference exists between method and device claims. Method or system claims vary in their language, too: in a system claim, components of the system are designed, i.e., configured; whereas in a device claim a component is designed to perform a unique function, i. e., to enable, or to be capable of - better yet - to enable a function.
In device claims use configured to and never able to.
Thus, the language for a valve:
a control device for enabling fluid communication between said electric mechanism and said collector upon demand.
More to follow.