IEC 60364 Table 48A

ProMbrooke:

Regarding touch voltage it is difficult to control as is. Reduced size CPCs, contact with earth, ect all present a voltage that is higher than assumed in Table 41.1. Thus, I am advocating for a touch voltage limit of 25 volts be established for wet locations with a disconnection time of at most 0.2 seconds for 230 volt supplies. 

 

1. It's always difficult to control touch voltage to Earth with a CPC. In fact, in TN-S systems, without main protective bonding it's difficult to control anyway. Unless you're advocating the distributor and/or consumer put additional electrodes in to help.
   
    

• I'm not really in agreement with you 100 % on the "wet location" argument. What kind of wet location, and what are the circumstances of the users? There's more to this than a simple table. As per previous posts, it depends on what you're wearing and whether saltwater wet is the issue or not. Under worst-case wet condition, sadly 0.2 s is not adequate. Worth having a look at IEC/TR 60479-5 This is the reason BS 7671 has other measures in places like bathrooms and swimming pools - including removing the hazard of AC mains completely by prohibiting it in some Zones. If you are erring on the side of caution to 100 % guarantee safety, it's goodbye to AC mains full stop I'm afraid.

ProMbrooke:

Regarding touch voltage it is difficult to control as is. Reduced size CPCs, contact with earth, ect all present a voltage that is higher than assumed in Table 41.1. Thus, I am advocating for a touch voltage limit of 25 volts be established for wet locations with a disconnection time of at most 0.2 seconds for 230 volt supplies. 

 

1. It's always difficult to control touch voltage to Earth with a CPC. In fact, in TN-S systems, without main protective bonding it's difficult to control anyway. Unless you're advocating the distributor and/or consumer put additional electrodes in to help.
   
    

• I'm not really in agreement with you 100 % on the "wet location" argument. What kind of wet location, and what are the circumstances of the users? There's more to this than a simple table. As per previous posts, it depends on what you're wearing and whether saltwater wet is the issue or not. Under worst-case wet condition, sadly 0.2 s is not adequate. Worth having a look at IEC/TR 60479-5 This is the reason BS 7671 has other measures in places like bathrooms and swimming pools - including removing the hazard of AC mains completely by prohibiting it in some Zones. If you are erring on the side of caution to 100 % guarantee safety, it's goodbye to AC mains full stop I'm afraid.