Testing GFCI?s & EFCI's:

[Tony S]

This is a follow on from the discussion about AFCI?s where EFCI?s (RCD?s) and GFCI?s (RCBO?s) got included in the general mix of things.


Press the button and see if it works method seems to be the accepted way of testing.

Now I?ll ask some questions.

Do you know the response time? It could be crucial when someone receives an electric shock.

Is the test circuit within its parameters? It could very well be faulty and tripping a 10x the rated current. Would you know?




This is the accepted method in the UK:

To test RCD?s and RCBO?s there are eight tests in total. Obviously for three wire 230V there will be more tests.

Four tests using the positive wave cycle, four using the negative.
The reason for using half cycle is some RCD?s have slightly differing characteristics for each half of the wave cycle. If there?s a major difference then it is time to change the unit.

The first six tests are for response times:
A1/ 0.5 rated tripping current +ve, this should hold indefinitely
A2/ 0.5 rated tripping current -ve, this should hold indefinitely
B1/ 1.0 rated tripping current +ve, this should trip within 300 mS.
B2/ 1.0 rated tripping current -ve, this should trip within 300 mS.
C1/ 5.0 rated tripping current +ve, this should trip within 40 mS.
C2/ 5.0 rated tripping current -ve, this should trip within 40 mS.

The final two tests are for the trip threshold where the test (fault) current is ramped up in stages to determine the point the RCD actually operates at. It should be around 23mA for a 30mA unit, below that and there?s the chance of spurious trips.
D1 ramp up +ve.
D2 ramp up ?ve.

The meters used for these tests can be set for the UK standard trip currents of 10, 30, 100, 300 and 500mA. Some of the more expensive units allow you to set your own parameters.


Someone please explain to me why ?pressing the button? is the better method.

Economic reasons will not be accepted as an argument, safety reasons only please.

An EFCI works exactly the same way as a RCD. If what goes in doesn?t come out then there?s a fault. It?s not rocket science.

 

[iwire]

Someone please explain to me why ?pressing the button? is the better method.

Economic reasons will not be accepted as an argument, safety reasons only please.

Then it is not worth talking to you about it if you have determined it is safety at all costs.

 

[ActionDave]

How many ways are there to say, Overregulation?

 

[Tony S]

Then it is not worth talking to you about it if you have determined it is safety at all costs.

Just the response I expected.

Come on iwire, you?re a moderator just as I am elsewhere. You can give a better argument than that.

 

[iwire]

Just the response I expected.

Come on iwire, you?re a moderator just as I am elsewhere. You can give a better argument than that.

You stated your mind was closed to a legitimate argument. Not much I can say.


How often is the testing you posted above done?

 

[ActionDave]

Just the response I expected.

Come on iwire, you?re a moderator just as I am elsewhere. You can give a better argument than that.

What does iwire being a moderator have to do with anything? You are the one that said expense can't be considered. As soon as that line is drawn there is no discussion.

 

[Tony S]

How many ways are there to say, Overregulation?

Try the NFPA-NEC if you want over regulation.

BS7671 is a recommended standard. You can be taken to court if you breach the recognised standard and cause injury/damage.

The first page of the NEC I do believe:

 

[mopowr steve]

How bout this,
The test button found on a device such as a GFCI is connected to the internal circuitry to create the parameters in which a device needs to be tested and pass unlike the test button on ,for say; a plug in neon tester with test button.
Now for sake of argument are you saying that the engineered test method for any device falls short of the testing you believe to be sufficient?

 

[Tony S]

Can we get back to logical discussion please.

 

[iwire]

Can we get back to logical discussion please.

How often is the testing you posted above done?

:?

 

[Tony S]

How bout this,
The test button found on a device such as a GFCI is connected to the internal circuitry to create the parameters in which a device needs to be tested and pass unlike the test button on ,for say; a plug in neon tester with test button.
Now for sake of argument are you saying that the engineered test method for any device falls short of the testing you believe to be sufficient?

You?ve hit the nail on the head.

From #1
Do you know the response time?
Is the test circuit within its parameters?

You don?t know the answers because you haven't done any testing.
What will happen in a court case, can you say hand on heart ?it worked? within set parameters. You can?t because you don?t know.

 

[mopowr steve]

Test the testing procedure? For compliance of parameters that need to be met.
sounds like an infinite kanundrum.
whats to say you don't then also need to test the very thing that tests what your testing?
And with a hand on my heart would then go after the manufacturers ( or the insurance company representing me) defect in testing if I unknowingly had a condition not of my fault which caused an incident.

 

[don_resqcapt19]

You?ve hit the nail on the head.

From #1
Do you know the response time?
Is the test circuit within its parameters?

You don?t know the answers because you haven't done any testing.
What will happen in a court case, can you say hand on heart ?it worked? within set parameters. You can?t because you don?t know.

If the GFCI device opens when you push the button, without holding the button for a couple of seconds, it is well with in the trip time requirements of the standard. It is assumed that a listed product has be built in a way that complies with the standard. The standard species the testing circuit.

As far as going to court, it is rare that an electrician would test a GFCI device after the initial install. We don't have any of the testing requirements here that you have. The instructions specify that the user test the GFCI once a month. We all know that doesn't happen, so effect the end of this month all new GFCIs have to be self testing. The are permitted to lockout the power on a failed self test but are not required to do so. They are also permitted to use an audible and visual indication that the device has failed the self test.

 

[romex jockey]

interesting...

interesting...

Someone please explain to me why ?pressing the button? is the better method.

Economic reasons will not be accepted as an argument, safety reasons only please.
.

No substitute exists for meticulous scrutiny of detail Tony

And btw, nobody here 'presses the button' except for maybe the inspectors , and those who need to reset the device(s)

But lets turn the tables.....

Imagine, if you will, a similarly detailed requirement for our gfci's , perhaps on some 3-5 cycle

How many of those older tenured models i see would really pass who's 'test button' in fact functioned?

~RJ~

 

[Tony S]

Out of interest, what are the prices for household insurance?

 

[iwire]

Out of interest, what are the prices for household insurance?

It is a big country with many rates.

My home is insured at about $165,000 and my insurance is about $1,800 a year.

 

[don_resqcapt19]

Out of interest, what are the prices for household insurance?

There are so many levels of coverage available that is a hard question to answer. Also part of it is based on the ISO rating of your local fire department.
Ours is full replacement costs for both the structure and the contents and runs about $3.5 per year per $1000 of coverage. It also includes personal liability.

The area you live in also plays a big part. Florida with the possibility of hurricanes has much higher rate than areas that don't have that risk. Our area has a risk of tornadoes and that increases the rate.

 

[mbrooke]

I think what Tony is trying to say, that testing GFCIs like done in the UK gives assurance that the GFCI is indeed functioning like intended. The test button doesn't even tell you the current imbalance much less the disconnect time.

 

[iwire]

I think what Tony is trying to say, that testing GFCIs like done in the UK gives assurance that the GFCI is indeed functioning like intended.

As does the test button

The test button doesn't even tell you the current imbalance much less the disconnect time.

I do not need to know that fluff to determine if the GFCI is functioning.

 

[Tony S]

I?m sorry gentlemen but testing is 2^nd nature to me. It means I can sleep easy in my bed at night (if it wasn?t for the insomnia) knowing what I?ve installed is safe and the protection will operate within the recommended parameters.

Doesn?t it ever bother you that you may have overlooked something. Something you would have found by spending a little time carrying out basic dead tests before energising a circuit.

Sorry if you find testing tedious and boring but keeping people alive is tedious and boring to the fire and paramedic services.