Hello,
The earth pin on UK plugs and industrial IEC EN 60309 connectors are longer to make the earth connection first and break last. This seems sensible but i have a question
I have several 19" rack enclosures that require interconnecting with power and control circuits. I cannot fit a typical power connector (eg 60309) but instead have found many other circular power connectors (eg Mil-spec) that are adequately rated and with designated earth pins, however, the earth pin is invariably the same length as the live pins i.e. the earth will not make first break last. This equipment is for use indoors, sockets less than 32A and with added protection with an 30mA RCD.
My understanding is that a longer earth pin is required under BS7671 but I can't actually find it stated explicitly any where in the regs. I'm probably not looking hard enough or is this a myth??
Can anyone point me to the regulation in BS7671 or other guidance notes where it states the earth pin must be longer than the live pins of a power connector? or is this implied where BS7671 states the use of IEC 60309 connectors - and it is in that standard where it states the earth pin must be longer? And just to be sure, would you agree that the use of 60309 connectors is not a requirement for indoor installations, but is for outdoor installations?
Thanks