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Pedantic semantics for earth fault

Hi All

I'm reviewing some of our documentation and it says "a 30 mA earth leakage circuit breaker" should be used.

Earth leakage breakers as such are no longer used, having been replaced with residual current devices. What wording do you think I should use? It seems to me that the fault to be detected is still "earth leakage" even if the device uses "residual current" as the detection method. So would I be correct to say "earth leakage fault protection, at a level of 30 mA"?

Thanks

Stephen

0 Rob Eagle over 9 years ago

Have a look at BS7671, 411.3.3 and 415.1, it states:

"..residual operating current not exceeding 30mA and an operating time not exceeding 40ms at a residual current of 5* operating current."

They seem to refer to it as residual current rather than earth leakage current now although that is where any loss of current is likely to have gone.

Rob
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0 Former Community Member over 9 years ago

So would I be correct to say "earth leakage fault protection, at a level of 30 mA"?

if you were pedantic (as I am) then you would not write "leakage fault" because that is a tautology (if current is leaking, by definition it is fault current)' and it's not really a level of 30mA its just a current (so more redundant words)

if you are using an RCD can't you just say

"protected with a 30 mA RCD"

Seems a bit simpler and to the point (for pedants like myself). When writing technical documents, less is always more; but if you were being complete, you surely need to state the minimum operating time and current too.
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0 Former Community Member over 9 years ago

So would I be correct to say "earth leakage fault protection, at a level of 30 mA"?

if you were pedantic (as I am) then you would not write "leakage fault" because that is a tautology (if current is leaking, by definition it is fault current)' and it's not really a level of 30mA its just a current (so more redundant words)

if you are using an RCD can't you just say

"protected with a 30 mA RCD"

Seems a bit simpler and to the point (for pedants like myself). When writing technical documents, less is always more; but if you were being complete, you surely need to state the minimum operating time and current too.
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0 Former Community Member over 9 years ago

So would I be correct to say "earth leakage fault protection, at a level of 30 mA"?

if you were pedantic (as I am) then you would not write "leakage fault" because that is a tautology (if current is leaking, by definition it is fault current)' and it's not really a level of 30mA its just a current (so more redundant words)

if you are using an RCD can't you just say

"protected with a 30 mA RCD"

Seems a bit simpler and to the point (for pedants like myself). When writing technical documents, less is always more; but if you were being complete, you surely need to state the minimum operating time and current too.
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0 Former Community Member over 9 years ago

So would I be correct to say "earth leakage fault protection, at a level of 30 mA"?

if you were pedantic (as I am) then you would not write "leakage fault" because that is a tautology (if current is leaking, by definition it is fault current)' and it's not really a level of 30mA its just a current (so more redundant words)

if you are using an RCD can't you just say

"protected with a 30 mA RCD"

Seems a bit simpler and to the point (for pedants like myself). When writing technical documents, less is always more; but if you were being complete, you surely need to state the minimum operating time and current too.
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0 Stephen Biddle over 9 years ago

Thanks, minimalist and accurate.

I hate redudancy, when people repeat what they just said using the same words, which are the synonyms of those already used previously.

Stephen
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Pedantic semantics for earth fault

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