in distribution boards and consumer units may have historically had their rated current determined after having taken diversity into account but without having considered overload protection of the devices.Ī collection of the latest guides relating to 18th Edition, Hager is proud to be a technical contributor to these guides which provide technical advice on a range of 18th Edition related topics.Īrc fault protection devices (AFDD) use microprocessors to identify characteristic current flow and voltage curves that indicate an arc fault and automatically trip the affected circuit.
RCD's exist in various different forms and react differently depending on the presence of DC components or different frequencies.ĭevices such as switches, RCCBs etc. In short this means anything from microseconds (millionths of a second) to a few milliseconds (thousandths of a second) in duration. Jocelyn Golding, Electrician Programme Manager at Schneider Electric, takes a brief look at five important amendments to the 18 th Edition Wiring Regulations.
A transient overvoltage or surge is a short duration increase in voltage measured between two or more conductors.
