From my understanding the six monthly test of the "Test" button is actually a "User" check. Now many on here will start saying cant have unskilled people accessing switch rooms and start pressing buttons that could affect sensitive supplies and cause more say production or financial issues.

But thats down to the Duty Holder to determine along with the helpful advice of an electrical practitioner.

So if somebody has been shown how to press the test button and the RCD/RCBO "Trips" to the off position then thats it, job done.

My understanding is all positive successful tests dont need to be recorded, it is only the RCD/RCBO units that failed to trip that would then be recorded, and unique company procedure would be to then call in a maintenance technician/electrical contractor to do some further investigation and likley use of a RCD tester.

I personally dont think it warrants comment or certainly a coded comment on a EICR. As long as the appropriate BS7671 label is present indicating Button pressed etc etc then thats compliant, A good contractor/inspector could have a conversation to ask perhaps because they can tell the six monthly test isnt being carried out, he has that conversation or sends a letter/report indicating buttons should be tested.

Of course if there is a simple log book/file same as testing the fire alarm weekly, that who, when, date, time the test was acrried out  and a signature then to me thats it, they could write "All Ok" and only ever then add what unit failed to work, and that then is followed up to persons who can action a electrically skileld person to further investigate.

I wouldnt code the button test isnt being carried out on a EICR.

If during a EICR the electrical inspector found a RCD/RCBO not working of course thats coded I would say a C2, if label for six monthly test missing a C3.

For a point of interest to people in my area of work on filling stations in our technical publications the test button on RCD/RCBO's should be pressed Monthly!! for all Haz area circuits simply because of the greater risk. So that means we have a modified BS7671 RCD Test button label applied that says monthly test not six months.

Frequency of formal testing during an EICR, unless the manufacturer of the RCD/RCBO stated in their instructions a more frequent pressing of the button or indeed formal RCD tests then thats what should be programmed in by Duty Holder and their electrical inspector/contractor.

BS7671 indicates the designer dictates frequency to the first EICR and thereafter its the actual electrical inspector carrying out the EICR that dictates the period to the next inspection.

Yes there are guidance documents and suggestions out there that indicate 3, 5 or whatever years, but its only guidance, so a high risk, wet  industry application with lots of unskilled people using electrical equipment, machinery, I would want frequency perhaps sooner than guidance indicates. Also age of the installation, would affect duration/frequency of EICR as a newer installation could in theory go longer between inspections than a 30 year old installation, but again thats something the EICR inspector should be taking into account when they make reccomendation to next EICR inspection.

Cheers GTB

What then is the remedial action that must be taken to rectify this potential danger?

Taken word for word from EICR:- 

“Introduce recorded maintenance test and inspection programme”

We have started recording trip times every three years and recording function tests every 6 months on a spread sheet. We have about 500 RCD/RCBOs on site. Not counting RCD socket outlets in control panels for programming use. 

I have no issue with recording trip times and functional tests, I just don’t think the absence of them is a C2, I doubt anyone would give a domestic EICR a C2 if there was no evidence of functional tests being carried out. 

But why would a "User Test" be coded as you listed in your comments?

I suspect you and JP are at cross purposes with the words and are actually in agreement. I think JP actually said "the user test device" rather than "user test" - i.e. he was referring to the T button - operation of which should be checked as part of ordinary BS 7671 RCD testing (col 29 of the schedule of test results).

  - Andy.

A very good point!

Press the test button and record the result, but hang on - you just did that as part of your EICR. :-)

The instrument tested at I delta n is the softer test than the test button. The user test facility tests the RCD at 2 x I delta n so should be done after the instrument test. If it passes the instrument test but fails the T button test then a C3 as the user cannot carry out the regular user test. Not unknown as the test resistor or sometimes goes open circuit but the RCD operates on a test with a test instrument.

JP

John Peckham said:

The user test facility tests the RCD at 2 x I delta n so should be done after the instrument test.

The current 2022 9th Edition of GN3 (Section 2.6.18) recommends the user test button is pressed before instrument test. It provides a reason why.

Basically, the test button uses "RCD test method 2" where a fault current is not returned to the protective conductor, but to one of the upstream live conductors. No-one else will be put at risk when the test button is pressed.

However, if RCD test method 1 is used, a voltage is present on the protective conductors of the installation until the RCD operates ... or the test instrument terminates the test. The voltage on the protective conductors may be limited by a test instrument to BS EN 61557, but:

• This is not guaranteed to protect everyone; and
• The voltage is not present when the test button is pressed (because it's 'Test method 2').

In addition, 'Test method 1' isn't possible for IT systems that use RCDs, for example.

Hi, if the test button fails to operate the RCD should you not proceed with the instrument test ? 

The test button is a zig-zag test, bridging between outbound live and inbound neutral or vice versa, and does not verify or requite  a CPC. However, being a higher test current than the minimum it may 'unstick' a mechanical RCD that would otherwise have failed a low current test.

If nothing happens when you press the 'T' button or equivalent, then your next act is to order up a replacement RCD/RCBO

You can still do a metered test if you like, but only on a modern meter that stops the test current before the test has run long enough to be dangerous to anyone downstream,

As the RCD has to be changed the test result is a bit academic.

Mike

Hi Mike. This is exactly what I do if the test button doesn’t operate. I have always marked it down as a fail and recommend it’s replaced without carrying out any further tests.

Andrew

AMK said:

Hi, if the test button fails to operate the RCD should you not proceed with the instrument test ? 

I wouldn't proceed with an "RCD test method 1" (fault current returned to cpc) test ... the RCD needs to be replaced anyway if the built-in test button doesn't operate it. If it's an internal electronics fault with the RCD, testing further could cause thermal damage (something might go "pop" or worse).

AMK said:

Hi, if the test button fails to operate the RCD should you not proceed with the instrument test ? 

I wouldn't proceed with an "RCD test method 1" (fault current returned to cpc) test ... the RCD needs to be replaced anyway if the built-in test button doesn't operate it. If it's an internal electronics fault with the RCD, testing further could cause thermal damage (something might go "pop" or worse).