I think the possibility of you passing 2391 is very remote - so if you don't mind I will not worry about you shoving it down my egotistical throat.Jesus I've never been so motivated to pass my 2391 only to shuv it down you eagertisticval throat!
You say you have done 2330 Level 1 & 2 (actually C&G aren't aware of level 1) and you are taking 2330 Level 3 and your NVQ.
But the evidence you have presented suggests you lack of even the basic knowledge of electrotechnical principles.
When this is coupled with your inability to properly explain yourself, in english, its hard to believe that you will have any chance of passing level 3.
Remember while 2330 level 2 was all about ticking the right boxes, 2330 level 3 and 2391 involves writing answers to the questions set in a way that the examiner will understand.
Without wishing to sound rude most colleges when assessing candidates for the 2330 course ask them to sit both english and mathematics computer based examinations.
The purpose of this is to assess the ability of the candidate to complete the course.
Once this assessment is made and where appropriate the candidate is given additional tutoring on his/her weak areas. May I suggest you would benefit from this additional tutoring.