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Best practices

MrJack96

Hi all can someone please give me some advice on the following? 

 

  1. say you’re maintaining a circuit and you realise parts of the circuits do not comply to the regulations what is the standard procedure for example ZS values that do not comply or IR that’s too low. I know in the industrial setting we are pressured to keep things going (critical kit) but say even if we’ve got it in writing we’ve said it’s potentially dangerous and we’ve been told in writing to switch it back on who is then at fault?

 

  1. say the circuit is an old installation and complied at the time of installation if we were then doing work on that circuit say for instance changing adding a spur to sockets that aren’t RCD protected what is the protocol with regards to bringing it up to current standard? 

 

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  • 0

    MrJack96: 
     

    The example I had was a motor circuit feed by 100amp bs88-2 fuses the Zdb was 0.20ohms and the R1+R2 was 0.28   ohms the cable from the panel to the local isolator uses the SWA as an earth. was in a situation where I refused to switch it on as it Doesn’t comply but Was seen as being a Jobs worth. 

    Is there no other protection for the motor which would disconnect it in case of an earth fault which could make it live for long periods?

    I can not imagine any scenario where a L. to E. fault inside a motor of a “bolted fault” type of negligible impedance, that would operate 100 Amp fuses, could occur, except perhaps the unlikely shorting of supply cables inside the motor terminal box.

    More information needed please.

    Z.

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  • 0

    MrJack96: 
     

    The example I had was a motor circuit feed by 100amp bs88-2 fuses the Zdb was 0.20ohms and the R1+R2 was 0.28   ohms the cable from the panel to the local isolator uses the SWA as an earth. was in a situation where I refused to switch it on as it Doesn’t comply but Was seen as being a Jobs worth. 

    Is there no other protection for the motor which would disconnect it in case of an earth fault which could make it live for long periods?

    I can not imagine any scenario where a L. to E. fault inside a motor of a “bolted fault” type of negligible impedance, that would operate 100 Amp fuses, could occur, except perhaps the unlikely shorting of supply cables inside the motor terminal box.

    More information needed please.

    Z.

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