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Initial Verification technical webinar

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Your questions answered

Any link to the video mentioned Grenfell tower individuals explaining their involvement? Or keyword to search for?

These videos can be found on You Tube if you search for Grenfell Enquiry

SY and YY cable is in common usage (esp by those involved in air-conditioning installs). Such cables are not covered by a harmonized, designated or international standard and are unsuitable for use externally due to their inability of their transparent sheath to cope with the effect of UV light. Some manufacturers cire a DIN 9German) standard but that only covers a very small part of the make up of a cable and isn't of the same level of coverage as either a harmonized or designated standard. their use is prolific so how are these passing the inspection by competent persons?

We believe that competent persons carrying out inspection and testing should be aware that installed equipment should comply with the requirements of Bs 7671 and in particular with Regulation 133.1.1.

Model Form for EICR on pages 201 and 202 doesn't seem to have a reduced et of inspection records?

No only the inspection form for Initial Verification has been reduced. Tyne Inspection form for EICRs remains and detailed form.

Do you think the x5 RCD test should still be completed as it is a fundamental test for the compliance for protection for life and otherwise how do we verify particularly older RCD are safe to continue in service with only. the x1 test BS 7671 only requires a X1 Test.

BS 7671 is a minimum standard and if you want, or think you should carry out additional tests then you should do so.

Is there a 6 month grace from 28th March new AMM 2, reason i ask is installation of AFDD's.

AMD is available for immediate use. The existing BS7671 plus AMD 1 will be withdrawn on the 27th of September 2022. You should not use the old standard as an excuse not to comply with the new standard.

(1) Should a voltage test be carried out between the DNO earth and main protective bonding conductors before they are connected to the MET.

(2) When testing Ze on an existing installation where main protective bonding is to be disconnected, a current measurement is carried out before disconnection with the main switch off, what value of current would you warrant as a danger and need reporting to the DNO/DSO

There may be a voltage between bonding and the DNO earth due to network circulation currents but it should not be more than a few volts. Depends on the size of the installation, the load on the network and the balance of the load on the network what current will be circulating under fault free conditions. If you are getting more than 4 or 5A a call to the DNO is advised.

If your MFT does NOT have a Type A setting, testing of RCD's on the AC setting are not required to be adjusted with x1.4 factor.

You do not need a Type A setting. BS 7671 only requires a X1 test at the tripping current as for a Type AC. On most occasions, unless faulty, the RCD will trip. If it does not then a further test at 1.4 x the tripping current is required as the RCD may be compliant with the product standard.

When deciding to undertake an insulation resistance test at 250v DC should your reasoning be recorded on the certificate?

The 500V test readings.

You could put SY/YY in plastic coated metallic flexible conduit and the UV wouldn't affect it.

It should not be used in any case as SY and YY does not comply with133.1.1.

An sy/yy cable be used for plug and socket arrangements for fixed equipment?

No use ordinary flexible cable or HO7RNF cable.

If sy and yy cable should not be used why is it within the AM2 and city and guilds assessments?

We do not know why this is in the AM2 test.

Page 63 GN3 r2 = 1.67 r2 ?? hopefully a typo? 1.67 x r1

Yes it is a typo.

Is performing less testing on RCD/RCBOs a good thing for the industry? What is driving it? Are we really testing the full functionality of Type A RCDs with an AC-test with wider tolerances?

BS 7671 only requires a X1 Test. BS 7671 is a minimum standard and if you want, or think you should carry out additional tests then you should do so.

Any tips on finding out Supply characteristics on larger installations when only carrying out small works.

Measurement is the best method.

Should there always be two people when carrying out the inspection and testing work? Any comments or opinions?

No. A risk Assessment needs to be carried out and from that a Method Statement should be written to determine if a second person is needed.

Not related to initial verification but what about insulation resistance testing vulnerable equipment during an EICR. Can you confirm voltages to be used?

On an EICR do not test between Live conductors only test between all live conductors connected together and earth. See IET Guidance Note 3.

Would you have to code a AC RCD on an EICR if electronic equipment installed?

Engineering judgement is required as it is your report and your signature. A C£ may be applicable unless there are aggravating factors.

If an RCD is there for additional protection, doesn't trip on x1 but trips in less than 40ms on 5x would that require additional test at 1.4 or could you accept additional protection is ok?

BS 7671 only requires a X1 Test. BS 7671 is a minimum standard and if you want, or think you should carry out additional tests then you should do so.

Enclosing SY or YY within containment doesn't make it meet harmonized, designated or international standards so simply shouldn't be used in fixed installations.

We agree.

SY is used in the AM2s to identify the departures, links in with I & T.

We do not know why this is in the AM2 test.

Guidance note 3 suggests 3 years between EICR for emergency lighting how do you test and indicate your recommendation if standard 5 year EICR is recommended for the building?

Emergency Lighting should have a monthly functional test and a Periodic Inspection and Test annually. See BS 5266.

With regard to AFDDs, is the term care homes only in relation to old peoples home?

No it could be children's homes etc. any where people are in residential care.

It is take account of manufacturer if MAN spec is S/Y... you judge?

It should not be used in any case as SY and YY does not comply with133.1.1.

What do you recommend how we approach the need for an additional earth electrode on PME installations getting a suitable ohms reading?

If this is for an EV charging installation then use the calculation in Chapter 722. If an ordinary installation the lower the better, no set earth resistance is required but try and achieve 20ohms.

When completing the Ze test we disconnect the earth and insert the figure on the EIC, on the SOTR, should the earth be reconnected and taken as a Zs @db and not the Ze figure used, even if this is the first point at the origin?

No we are just proving we have the presence of an earth and it is of a suitable impedance.

Are AFDDs to be installed on all Circuits or just Socket circuits?

Only where they are required as compulsory in BS 7671. It is recommended that consideration be given to installing them else where.

In relation to AFDD's, I have a client who has several wedding venues which only have guests stay for 1 night. Do you think these would meet the requirements to have AFDD's as standard?

No definite requirement to fit them. It is recommended that they be fitted to other circuits. If there are particular risk in the wedding venue the client may wish to have them fitted.

Re care homes - don't forget Children's homes.

Children's homes are care homes. Any residential home with people in care is a care home.

When we advise a client to have AFDD installed and they refuse must we get it in writing?

If AFDDs are required in one of the 4 "shall" locations they cannot be refused. In other places if the client refuses after they are recommended then get the refusal in writing.

AFDD can be a benefit for heritage risks etc.

Yes a good idea - thing about the fire at Clandon House.