Recently done 2391-52
Did it one day a week for several weeks as couldnt take a week off so not rushed, felti benefited more because of it.
Did it with morris services in kingswood.
Found it insightful from periodic point of view and how the chief examiner at city and guilds codes things c1 c2 etc and why.
The actual testing side was no drama and didnt really test the whole system, told what to test by the supervisor. You have to demonstrate a range of testing and examiner must be satisfied you know what you are doing.
Found it good brushing up on volt drop, and other calcs as im a bit of a maths nerd.
As always safe isolation is a must so make sure you know how to isolate a 3 phase board.
Had 3 faults on mine 1) high resistance water bonding >5ohms
2) L1 missing on DOL starter found doing polarity check
3) IR test between conductors on socket circuit below 2Mohm
Had series of posters showing installations and had to identify issues c1,c2,c3,fi or none. One of them has no issues. Nothing too difficult. Think it was 8 posters in all.
Written part is easy, simple couple line answers, nothing a first year college kid wouldnt fly through. If in doubt just go to gn3 and the example inspection schedules and it gives you a reg number for each issue on an eicr!
Didnt find the computer exam too bad. If you know your testing and are upto date with the 18th you shouldnt struggle. Dont rush it and watch how the questions are written. They like scenarios with say 5 questions for it.
The 2391-52 is 60 questions across both initial and periodic where as the 50 and 51 are 40 on the respective area. Tutor reclons the 52 is easier.
The practice exams are a good indication of the real one in terms of difficulty.