brucelee
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Hi all,
could someone clear a few things up for me as i have my 2391 next thursday
1. If earth fault loop impedence to high is it code 1 or code 2
2 If asked to explain procedure for PFC on a three phase board do i need to include
Testing between all lines and earth as well as all lines to neutral
as the highest three phase pfc will always be between the lines so to find this have to double the highest L-N value by 2 so do i include testing lines to earth
3 Could someone explain the reasons for selecting the following
i). Low resistance ohmeter
is it because we are expecting low values of resistance?
ii). insulation resistance ohmeter
is it because we are checking no dead shorts or defective insulation
iii). earth fault loop impedence tester
is it because its capable of checking the earth fault loop is sufficiently low enough
iv). pfc function of an earth fault loop impedence tester
to check the amount of fault current that could flow under fault conditions to compare against breaking capacity of protective devices?
v). rcd tester
to check the rcd will operate in the event of a fault
vi) What type of inspection for a existing installation
is it a periodic inspection and test or a periodic inspection report which i think is wrong and its the first of these?
Also for scales and ranges
eg is ohms, Mohms,etc the scale and eg for low resistance ohmmeter the range 0.02 - 2ohms could someone clear all this up for me if possible much appreciated thanks
could someone clear a few things up for me as i have my 2391 next thursday
1. If earth fault loop impedence to high is it code 1 or code 2
2 If asked to explain procedure for PFC on a three phase board do i need to include
Testing between all lines and earth as well as all lines to neutral
as the highest three phase pfc will always be between the lines so to find this have to double the highest L-N value by 2 so do i include testing lines to earth
3 Could someone explain the reasons for selecting the following
i). Low resistance ohmeter
is it because we are expecting low values of resistance?
ii). insulation resistance ohmeter
is it because we are checking no dead shorts or defective insulation
iii). earth fault loop impedence tester
is it because its capable of checking the earth fault loop is sufficiently low enough
iv). pfc function of an earth fault loop impedence tester
to check the amount of fault current that could flow under fault conditions to compare against breaking capacity of protective devices?
v). rcd tester
to check the rcd will operate in the event of a fault
vi) What type of inspection for a existing installation
is it a periodic inspection and test or a periodic inspection report which i think is wrong and its the first of these?
Also for scales and ranges
eg is ohms, Mohms,etc the scale and eg for low resistance ohmmeter the range 0.02 - 2ohms could someone clear all this up for me if possible much appreciated thanks
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