hey i dont supose any one can help me with these questions

[wesleyharrison]

hey all i have some collage questions and would be great if you could help me out as im stuck on these two which are as follows

subject 'test & inspect'

1) what are the approved procedures and requirments for commissioning the installation?

2) how would you carry out the tests and what is there effect on equipment that isnt part of the fixed installation?

thanks all

 

[initforthemoney]

Gn3 is your friend.

 

[Badger]

hey all i have some collage questions and would be great if you could help me out as im stuck on these two which are as followssubject 'test & inspect'

1) what are the approved procedures and requirments for commissioning the installation?

2) how would you carry out the tests and what is there effect on equipment that isnt part of the fixed installation?

thanks all

1) the testing would be Insulation resistance to check between live-neutral/live to earth and neutral to earth to check for shorts or resistance between thos paths, ie from moisture or damaaged insulation between the lve/neutral/earth.

continuity on ring fianls to make sure they are end to end connected between l n e and r1 and r2 to check for polarity of the live supply through switches etc, and also to make sure that the earthing is continuos and theres no breaks on the earthing.

earth loop fault impedance to check to make sure the earth resistance to earth path is with limits for the mcb/provtective devices operating amounts.

rcd testing to check that rcds operate in times of under 200 ms for x1 and under 40ms for x5 the rcd, the rcd should be checked through both 0 degrees and 180 degress for functionality and the highest result should be recorded for both x1 and x5, also rdcs should be checked for 1/2 rated tripping to make sure at (for example) 30mA rcd dont trip at 15 mA

hope that helps.

2) all equipment should be unpled or switched off as insulation resistance is checked with double the circuits voltage ie 230v installations are checked at 500v DC and sensitive equipment like alarms etc and computers can be damaged on the electronics.