Consumer units comply with 17th Edition

Hager has launched a range of consumer units to meet the requirements of the 17th Edition of the Wiring Regulations. Steve Dyson, product manager with the company, explains, ‘The new regulations will change the way that contractors plan and install the final circuits to the consumer unit. The easiest way to comply is to ensure that all circuits have RCD protection. In addition, they must ensure that circuits are divided and that not all are connected to a single RCD. ‘In practice, there are several different ways that this can be achieved in the consumer unit. These new boards give the contractor different options for compliance.’ The simplest way to comply is to install a board with a main incomer switch with RCBOs (residual current circuit breaker with overcurrent protection) protecting all the outgoing circuits. Hager has also introduced a range of 4.5 kA RCBOs suitable for domestic applications. These boards are available with four to 20 outgoing ways. The second option is a split-load board with twin RCD protection. A dedicated 6 A RCBO is used to protect the smoke-detector circuit. These boards are available with a 100 A mains incomer and either two 63 A RCCBs (residual current circuit breaker) or two 80 A RCCBs with 10 or 14 outgoing ways. Another option is a split-load board with twin RCCB protection. These are again available with 63 or 80 A RCCBs. Here, the smoke-detector circuit is protected by one of the RCCBs, which can also supply circuits such as lighting but must not feed socket outlets. Careful arrangement of the other circuits can reduce the chance of nuisance tripping, but there is a certain amount of compromise that the contractor must accept with this arrangement. The fourth option from Hager is a split-load triple RCCB board. It has two 80 A RCCBs and a 40 A RCCB with a 5x5x2 outgoing way split. This arrangement provides an RCCB for the smoke-detector circuit that can also be used to supply circuits such as lighting. The final configuration is to use a split-load board with twin RCCBs plus an unprotected circuit. If the smoke-alarm circuit is not protected by an RCCB, it must be installed using a method from regulation 522.6.6. Hager offers a free consumer-unit guide to the 17th Edition.
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