Hager has produced a free consumer unit guide to the 17th edition wiring regulations. It outlines the new requirements for domestic installations and suggests what solutions the contractor should consider.
It states that the biggest change faced by the contractor is that they need to consider RCD protection across all of the circuits. While there are alternatives, this is the most cost effective way of complying and it means that they must consider alternative consumer unit configurations.
The guide points out that all of the circuits should not be connected to a single RCD, since this could lead to the loss of supply for the entire installation if there is a fault on one circuit. Protection for a smoke detector circuit also needs special consideration.
Hager’s Product Manager Steve Dyson comments: “The introduction of the 17th edition of the wiring regulations has major implications for all electrical contractors, designers and consultants. This guide outlines how the new regulations will affect final circuits and the consumer unit in a domestic installation. It takes a practical look at the relevant sections and then shows ways of complying.” 
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