RCD's and how they should work

[nickblake]

OK chaps RCD's we all know what they do ,they work if a fault to earth is detected basically an imbalance ,my concerns about these is that recently ive had three gardening tools in all class 2 two core , cables cut in half , didnt blow the fuse or trip the RCD so live ends floating about ,me being me sent a letter to the ESC sugesting earths should be in class 2 appliance cables ,got a reply back saying they dont need an earth because the RCD will trip if touched by some one touching the live end of the cable ,bit shocked at the reply
but before i reply just wonder what your thoughts were on this ill post the full reply at a later date

 

[acat]

Dont particulary want to test it myself but what they say is true if you touch live you become the path to earth causing the imbalance DEEP JOY


Chris

 

[Phil]

i will tell my customers not to press the test button to check the opperation of the rcd then i`ll just tell em to go do a bit of gardening and touch the live end`s. priceless

 

[Cj24]

Yeah that don't sound good to me there should be an earth too, can you please tell me the difference and where they would be used between an rcd and an rcbo please

 

[Phil]

i hope they are not one of the 4% that fail though
RCDs put to the test | Industry Press Releases | Electrical Safety Council

 

[mogga]

when RCD sockets started coming into fashion a wholesalers near em use to demonstrate by licking his finger and touching end of cable to "Show them it was safe" he never flinched but noone took him up on his offer to try it lol

 

[acat]

Just like part P we will have to wait until an MP or relative of an MP gets a shock then all electrical items will have to be earthed by law and that law will be as precise as part P


Chris

 

[davelerave]

the rcd can protect against

-fire/dangerous fault currents in the installation
-'automatic disconnecton' if needed
-trip on 'direct contact'

cutting a 2-core lex will trip the circuit mcb

you're making a god argument for screened /armoured leads mind you

 

[Phil]

did you attend the funeral or is he still clamped onto the cable in the corner

 

[Sintra]

the rcd can protect against

-fire/dangerous fault currents in the installation
-'automatic disconnecton' if needed
-trip on 'direct contact'

cutting a 2-core lex will trip the circuit mcb

Or the fuse in the plug.

 

[davelerave]

how exactly did you cut the 2-core leads without causing a short circuit

 

[davelerave]

Or the fuse in the plug.

ya sorry forgot

 

[Deleted member 9648]

If you touch the live end you may become the earth conductor....but the reason for a 30ma RCD is it has been shown that a shock current of 30ma has not proved serious. When I was at college the tutor said that even 100ma rcd's and 100ma shock current had never proved fatal.
(there is a case to be made though that anyone daft enough to pick up the end they have just cut deserves a good handful of sparks)

 

[davelerave]

the only improvement i can think of on a class2 appliance outdoors is a screened flex maybe

a cpc or a class1 appliance is no help

an isolated supply is prob theoretically safer as L-N contact has the same effect for both supplies


anyhow if you managed to cut through 2-core leads and sill have live wires everywhere you're either paul daniels, or you have a serious electrical problem,or your leads are like 2km long

 

[Cj24]

Rcd? And rcbo what's the difference, thanx