permissif d'ouverture

20:52 Jan 23, 2017 

Great, that's already a good guide: for a start, we can see that this 'permissif' is soemthing upstream of the actual 'commande'. It also talks about 'state', so it looks like we are dealing with logic, in which case, an 'enable' would be perefectly appropriate here. It is made clear that this PF is a 'signal', so to me, it is an 'enable signal' that allows the command to go through

20:41 Jan 23, 2017 

Thanks everyone for your contributions so far. It's definitely a noun and also appears in the following sentence further on in the text:
Quel que soit le mode de fonctionnement de l’algorithme (auto ou manu) et quel que soit l’état du permissif de fermeture (signal FP), une commande de fermeture d’urgence sera exécutée (passage du signal CMDF à l’état 1) si le signal FU est à l’état 1.
There's also a screenshot at the end showing an empty box on a control panel with the legend "Permissif de fermeture absent".
I think I am going to have to check back with the client.

20:11 Jan 23, 2017 

BTW, if this is something physical that allows something else to happen, I'd tend to use 'allow' rather than 'permit', which seems to me to suggest more of an abstract authorization. "The hinge that allows the door to open".

20:05 Jan 23, 2017 

FR is able to use an adjective standing alone as a noun in a way that we generally can't do in EN (except with e.g. abstract adjectives forming a collective noun, such as 'the poor / elderly / homeless' where 'people' is understood)

So here I believe you need to interpret this as '[thing that is] permissif d'ouverture' — the trouble is, knowing just what sort of 'thing' it is! You could of course always try something invented like 'opening allower', converting it from an adjective to a noun by going via a verb! Cf. 'door closer'. But I really wouldn't recommend such a course of action, other than in one's head ;-)

The ideal thing would be to see if there are any other clues later in your text that might shed light on it; or of course ask your customer!
Failing that, all I can think is to imagine it as if it were 'dispositif' etc. and treat it as 'unit', 'system', 'module', etc. — but that's getting into risky territory, since it might be over-translation or be a bit skewed from the real meaning.

Possibly you will find clues in the rest of your document, in the other list items, for example?

20:03 Jan 23, 2017 

Permitter?
And are you sure it's a noun?