There are a few approaches (in general, nothing specific to Amtech) - reduce the impedance upstream - e.g. increase the cable size (although that may not be possible if the problem is at or close to the intake), reduce the rating or type of the breaker, or switch to a different approach for ADS - e.g. RCD or earth leakage trips.

In theory you could go down allow >5s disconnection times and add supplementary bonding to keep touch voltages below 50V - although that's unusual, likely to raise a lot of eyebrows, and typically isn't very practical in other than small contained situations.

As a rule of thumb though, if Zs is too high for typical breakers in a TN system and c.p.c.s aren't substantially smaller than the live conductors, then you're very likely to be seeing voltage drop issues too - in which case a bigger review of the design might be in order.

   - Andy.

There are a few approaches (in general, nothing specific to Amtech) - reduce the impedance upstream - e.g. increase the cable size (although that may not be possible if the problem is at or close to the intake), reduce the rating or type of the breaker, or switch to a different approach for ADS - e.g. RCD or earth leakage trips.

In theory you could go down allow >5s disconnection times and add supplementary bonding to keep touch voltages below 50V - although that's unusual, likely to raise a lot of eyebrows, and typically isn't very practical in other than small contained situations.

As a rule of thumb though, if Zs is too high for typical breakers in a TN system and c.p.c.s aren't substantially smaller than the live conductors, then you're very likely to be seeing voltage drop issues too - in which case a bigger review of the design might be in order.

   - Andy.