Pirform now has a new feature that allows you to disregard high Zs readings for TT installations. This feature must only be used if the requirements of Regulation 411 in relation to disconnection by means of an RCD has been met.
How does it work?
If your installation has a RCD as a main switch, you can select the “Disregard Zs for this certificate” option. Now, when entering values that exceed the maximum permissible, the intelligence will not trigger.
If you do not have an RCD as a main switch, but have a particular board that is protected by an RCD, then select the “Disregard Zs for this board” option.
If there is a split board, and only some of the circuits are protected by an RCD, then individual circuits can be selected.