IAEI Weekly Update Article ?Mandatory safety switch to save lives?

[mweaver]

In this weeks? IAEI weekly update (March 18, 2009) there is an article titled ?Mandatory safety switch to save lives?. This article tells a tragic story (this one is from Australia) many of us have heard (way too many times...) in one form or another, but the article also discusses (while only briefly?) the mandatory switch.

They state:
?Safety switches detect minute changes in the electrical current balance of a circuit, so that if a person touches a live part of an appliance or cable accidentally, the safety switch trips the circuit rapidly.?

My question:
Are they referring to a switch similar to what is utilized often in Eurpoe and is called an ?RCD? (Residual Current Detector??); or are they just talking about a branch circuit GFCI ??


My understanding (Which is about nonexistant on this...) is that an RCD is basically a feeder type GFCI which operates in the 30ma range?

Any expanded explanation would be beneficial to me?

mweaver

 

[dbuckley]

RCDs are used in Europe exactly as GFCIs are used in the USA. The only difference is the trip level: 5ma stateside and (for personel protection) 30ma in Europe. Some years ago I read that there had never been a fatality from shock when protected by a 30ma RCD.

So, you can get RCD recepticals, RCD breakers to go in panelboards, and RCBOs which are a combination of RCD and OCPD.

Here in New Zealand we've got a stupid rule that says all new houses have to have the sockets and lighting protected by RCD, so most installations are minimally compliant, ie one RCD for all of the lights and sockets. So if the trip the RCD you are floundering around in darkness... if it goes while you're on holidays then thats the freezer trashed.

Dumb.

 

[bphgravity]

Get yourself a copy of the book, "Overcurrents and Undercurrents - All about GFCIs, AFCIs, and Similar Devices - Electrical Safety Advances Through Electronics" by Earl W. Roberts.

It is one of my favorite references.

 

[mweaver]

Dbuckly & Bryan,

Thanks for your response and input. It is certainly helpful.

On your suggestion of the reference material: ?"Overcurrents and Undercurrents - All about GFCIs, AFCIs, and Similar Devices - Electrical Safety Advances Through Electronics" by Earl W. Roberts?? Bryan; I just happen to remember this publication is available for order from IAEI, so I am on it.

Thanks again guys,

mweaver