Modding SEV Thread Questions

[President_Elect_Shang]

I�m a little confused here, I see this descriptor however how does SE5 know to only place one per ship?

Ability 3 Type := Description Only
Ability 3 Description := Only 1 Survey Instruments per vehicle effective.
Ability 3 Scope := Space Object
Ability 3 Range Formula := 0
Ability 3 Amount 1 Formula:= 0
Ability 3 Amount 2 Formula:= 0

Is there another entry that controls this, there must be but what is it? What is the limit for how many I can place; as in SE4 where I could place up to 10 per?