meerkat
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Hi, just passed the 2392 and have the following advice for students sitting the exam.
Ask for any paperwork regarding installation/Consumer unit at the start.
Do the safe isolation:
6. R rcd test set at 30mA (1) 0.5 x full load no trip 2 secs, retest at 180 no trip 2 secs, (2) 1 x full load trip in less than 300m secs, retest at 180, trip in less than 300msecs, record highest reading for x 1 reading. (3) 5 x full load test trip in less than 40msecs, retest at 180, trip in less than 40msecs record the highest reading as x 5 reading, (4) test Rcd self test button, must trip RCD.
Covers on, complete functional tests on all circuits.
Complete paperwork and fill in readings obtained on schedule of test, compare max Zs readings for type of circuit breakers/fuses used with those in the OSG or using the Rule of Thumb calculation using the figures in the BRB.
Make a note of any discrepancies found in the box at the bottom of the schedule of test tables or in the comments on existing installation box page 2.
I found:
Good Luck and try to remain calm.
Go to pub and celebrate for the whole night!!!
Hope this helps (Meerkat)
Guinness Guinness
Ask for any paperwork regarding installation/Consumer unit at the start.
Do the safe isolation:
- Identify means of isolation
- Ask permisssion to isolate
- Isolate and lock off
- Inspect and prove voltage tester
- Test circuits dead between L/N L/E N/E
- Reprove voltage tester
- Post warning notices.
- Remove all covers and inspect
- complete the inspection sheet
- Replace all covers except the CU
- Partially complete testing sheet with circuit details
- Start testing using the acronym C.R.I.P.E.R
- Continuity of cpc's and MEBC water and gas input readings in r1+r2 box on schedule of test sheet for radial circuits.
- Ring final circuit continuity, (1) r1, rn, r2, (2) cross link L/N x 2, (3) cross link L/E x 2, compare readings as a guide eg R1+R2/4 input reading obtained on schedule of test for socket circuit R1+R2.
- Insulation resistance test, remove anything vulnerable to the test, eg neon's, lamps, transformers etc (Global) set @ 500V DC and 200Mohms test between L/N once, L/E twice incorporating the strappers of 2 way lighting, N/E once, anything less than 2Mohms on a global test means there's a latent defect somewhere.
- Polarity done for radial circuits at C, Ring circuit continuity at (3)
*Live Supply polarity should now be confirmed using a suitable voltage tester L/E 230v L/N 230v N/E 0v, before energising the system
- E Live testing be careful, (1) Ze, first isolate supply, disconnect main earthing conductor in CU test between disconnected Earth and incoming Line and Neutral, 20ohms setting, reconnect earthing conductor. (2) PEFC set at 2000amps same test as (Ze) with earthing conductor connected . (3) PSCC set at 2000amps test between incoming Line (red probe) and Neutral (black probe) attach the green probe to the Neutral rail and link in by closing the main isolation device. make sure all mcb's and RCD are in the open/off position before closing the main isolation device.
6. R rcd test set at 30mA (1) 0.5 x full load no trip 2 secs, retest at 180 no trip 2 secs, (2) 1 x full load trip in less than 300m secs, retest at 180, trip in less than 300msecs, record highest reading for x 1 reading. (3) 5 x full load test trip in less than 40msecs, retest at 180, trip in less than 40msecs record the highest reading as x 5 reading, (4) test Rcd self test button, must trip RCD.
Covers on, complete functional tests on all circuits.
Complete paperwork and fill in readings obtained on schedule of test, compare max Zs readings for type of circuit breakers/fuses used with those in the OSG or using the Rule of Thumb calculation using the figures in the BRB.
Make a note of any discrepancies found in the box at the bottom of the schedule of test tables or in the comments on existing installation box page 2.
I found:
- no brown sleeving on strappers,* cracked socket front,
- 3 circuits failed due to high Zs readings, when compared with acceptable max Zs figures on page 49 of the BRB remember the rule of thumb x 0.8 of actual figures in the BRB, rule of thumb not reqd for figures in the OSG.
Good Luck and try to remain calm.
Go to pub and celebrate for the whole night!!!
Hope this helps (Meerkat)
Guinness Guinness