The recently introduced Construction Products Regulation (CPR) lays down harmonised rules for the marketing of construction products in the EU according to the product standard EN50575:2014.
Starting from 1st July 2017, all products must be CE marked and they must have a Declaration of Performance (DoP).
Information from SG22
SG22 is a Sector Group under the EU, which originated as the subgroup SH02/WG10.
When Notified Bodies are unsure how to interpret the CPR standards concerning cables, they can ask SG22. The Sector Group will then discuss and provide an answer. Subsequently, all Notified Bodies are obliged to follow the interpretations presented by SG22.
Below is a list of questions asked by Notified Bodies and the answers provided by the SG22 group (updated July 2019).
Question from NB
Answer from SG22
Should a change of colour (jacket) required to consider a different cable family? No, as stated in TS 50576 As a notified body, are we allowed to issue a classification for a class lower that the one corresponding to the results? (to “downgrade” the family, e.g. Dca instead of Cca); Yes What must be done whenever the manufacturer changes the supplier of one of the materials constituting the cable: are some checks required or is it the responsibility of the manufacturer to claim that the change of supplier does not affect the fire performance? Part of it will be related to FPC where the manufacturer will have to demonstrate that the change of supplier has no influence (based on test data). Of course, this is provided that the “generic” component remains the same (e.g. PE from X to PE from Y). If the demonstration from the manufacturer is not satisfactory then a new test shall be performed. For power cables with a diameter ≤ 5 mm, the understanding is that every size in EN 50399 should be tested. This could lead to a very large number of tests. Couldn’t (shouldn’t?) we agree on simple rules to select a limited number of sizes (2 or 3) and for safety margin (e.g. 20 %) at this stage? No.
NBs shall follow the EN standard and position paper. No deviation can be accepted outside of EXAP or position paper.
In addition to the previous point on EN 50399, can we consider all the sizes for a given type of cable (i.e. including cables with OD ≤ 5 mm) as a single family, or 2 families ( OD ≤ 5 mm and OD > 5 mm)? Two families. Cables ≤ 5 mm are not covered by EXAP For the EN 50399, how to deal with cables with diameters ≤ 5 mm within families for which EXAP is used ? They have to be tested individually Classification a3 : is this a NPD? Or is it necessary to perform EN 60754-2 test ? (cf. Euroclass F in the Delegated Regulation) For a3: classification, NPD can be used Cables constructed by fixing 2 (identical) cables side by side: should they be considered as a different family? (to link with answer for cables diameter < 5 mm) They are 2 different families Are cables with fire protection “coating” (in order to improve their reaction to fire) considered as cables covered by EN 50575 ? Yes, if the cables is produced and placed on the market with the coating
No, if the cable is protected after being placed on the market (in a such case the cable without the coating shall be CE marked)
In a family with 2 cables where Dmax-20% = Dmin, do we need to test 2 cables? The 2 cables shall be tested Are blind elements also considered as units for FOC? No,
a unit has a fibre in it.
If parts of (same) complete products are subcontracted within the same company, is any testing and/or inspection of these products needed? No testing is needed if the same materials and processes are used, but initial inspection is needed in every production site. Continuous inspections may rotate depending on the FPC systems and production process. Is the EXAP identification under the responsibility of the manufacturer or of the NB? As the EXAP is part of the assessment of performance, it is an NB responsibility to ensure that the familly defined in the classification report is in line with the rules (EXAP, BP, or PP) Power and communication cables: In terms of definitions, what are the limits in terms of voltage for each type of cables ? Power cables in EXAP – for CCC no more than 50 V rating and over that the manufacturer has to specify the application. The type of cable will be specified in the test and classification reports and the certificate when applicable. If a family is (using EXAP rules) qualified for example class D, but one (or both) of the test samples itself fulfils also class C -Can a classification report on class C for the individual cable be issued in addtion to a classification report D for the familly? Yes, but the C classification report can only be used for CE marking if the sampling has been done under the responsibility of the NB Audit testing: is a safety margin being added to the results (in case of a cable family)? No – the test is for the evaluation of the class of that cable Can a manufacturer consider the audit testing as yearly test for the FPC? No,
audit testing and FPC are different
Classification report: can a classification report contain for one familly different classification (e.g. small diameter having a different class etc.) Yes : Agrement between the NB and the Manufacturer In § 188.8.131.52. of EN 50575, it is written that the frequency of the Fire testing can be reduced subject to provisions given in 6.3.3.
What does this frequency reduction mean and in what case could it be applied?
The reduction can be considered after 2 audit test periods and considering the additional control performed.
The classification shall remain the same within the 2 audit test periods.
If a manufacturer does the yearly testing in a lab not known to the Notified Body issuing the certificate – is there any qualification of this lab necessary? By whom? This is under the FPC evaluation and the NB shall evaluate the equipment and the personnel qualitification of the laboratory. (If the manufacturer decides to change the supplier of testing the NB shall be informed before the change is made) On acidity: In principle each combustible material included in the cable must be tested individually. IEC 60754-2 includes in a note ((in § 1)
NOTE: The relevant cable standard should indicate which components of the cable that should be tested, and which method of calculation (see Clause 8) that should be used in case of dispute.
Material for which the relative mass is ≤ 1 % of the total mass of combutible materials does not need to be tested for acidity according to EN 60754-2. On acidity: For non halogonated UV-additives in compound, what is the acceptable amount for not considering the compound as different? Non halogenated UV-additives with a relative mass <1% of the compound is considered as the same compound Is it mandatory for Notified Bodies to keep reference samples from testing? If yes, which length and for which duration? It is not mandatory, but recommended for a time period of at least 3 months Cable types in one EXAP family need to be made of the same materials. Does this mean that cables with copper and aluminium conductor (and/or screen) cannot be put into one family? Yes they are different famillies Are cables with or without interstitial filler to be treated as different EXAP cables? Are cables with or without filling compound to be treated as different EXAP cables? For interstitial filler other than center filler and/or filling compound: the cables are considered as different families If a cable family is tested according to class D or higher (= including EN 50399 test), but due to the results, only class E is possible, does still the cable parameter has to be mentioned in the classification report or the cable diameter (= rules for class E)? The test according to requirements from class Eca has to be performed according to EXAP rules for class Eca which could mean extra tests have to be performed. The market for CPR cable tests under system 3 has an increasing request for the release of “Attestations of Conformity”. Is this permitted according to CPR? Under the CPR, NBs are only allowed to issue under AVCP 3 test and classification reports (when applicable) and under AVCP 1+ in addition to the test and classification reports the Certificate of Constancy of Performance. This is related to communication cables: control cables. When I looked at the standard it is written:
Note1 : Multicore power cables with more than 5 cores are sometimes referred to as control cables with a rated voltage but for the purposes of this standard are considered as power cables
What about the control cables which have the core below 5 ? Which product family they should be considered in ?
They are considered as power cables (for core below 5) and they are considered as the same family. Cables mixing power and communication conductors are now available. Are EXAP rules applicable to such cables? If yes, which ones? General EXAP rules will apply (hybrid cables) for testing according to EN 50399 A cable family shall fall under one of the generic communication cable families:— U/UTP unscreened overall / unscreened twisted pair — F/UTP screened overall / unscreened twisted pair;
With such a statement, it excludes communication cables such as coax cables and telephone cables. Should we conclude that at this stage EXAP cannot be applied to these cables?
Telephone cables are covered by EXAP rules for testing according to EN 50399
For coax, all cables in the family shall be tested to EN 50399 (as no data are available for defining EXAP rules)
Non circular cable (EN 50399): What is the definition ? First refer to the product standard; if there is no rule then the following will apply:
Maximum ovality of a circular cable, based on min and max diameter of the cross section, to be determined. The difference between any 2 values at the same cross section shall not exceed 15% of the overall diameter. (EN 50525 series)
About “twisted cables”: Some manufacturer place on the market bundles of cables, consisting of a limited number of individual (identical) cables (3, 5, 7), possibly twisted and fixed together by strips or equivalent. If The individual cable has obtained a Euroclass (and is CE marked), what about the assembly ? Should it be considered as a distinct product and require the complete set of tests to be performed? Individual cables shall be tested For non-circular 8 figure cables below 5mm, no testing procedure is defined in EN 50399. Is there any solution how to test these cables nevertheless according to EN 50399? There is no general solution. Tthe cable is a figure 8 cable, consisting of two identical round cables with Diameter D, being fixed with a small nose-piece between them. Then the cables can be tested like round cables (in bundles) with Diameter D, with half of the samples. So the only difference to testing the round cables is that within the bundles, each cable is “connected” to one other cable, which is not relevant for testing. For non-circular cables below 5mm excluding 8 figure, no testing procedure is defined in EN 50399. Is there any solution how to test these cables according to EN 50399? The cable is only slightly different from round shape (major axis a to minor axis b ratio less than or equal to 1.5). Then for the non-circular cables, the surface can be calculated in good approximation as Deq=sqrt(minor*major). When tested acc. to EN 60332-1-2, some cables are broken before the test is completed or small cables that fails the test (melt before the test is completed). Are there any provisions in the standard for that situation? In these cases, the procedure stated in the scope of EN 60332 part -1-2 shall be applied. The addtitional test standard used for the test shall be stated in the test and classification reports. EXAP for audit testing : Must all cables of diameter lower or equal to 5.0 mm be tested every 3 years ? For the audit testing and annual testing : one of the cables with diameter lower or equal to 5.0 mm shall be tested and one with a cable diameter included in the EXAP rules About “twisted cables”: Some manufacturer place on the market bundles of cables, consisting of a limited number of individual (identical) cables (3, 5, 7), possibly twisted and fixed together by some strip or equivalent. I The individual cable has obtained a euroclass (and is CE marked). What about the assembly: should it be considered as a distinct product and require the complete set of tests to be performed? For Eca, each individual cables shall be tested About cables for wind turbines; Are the torsion resistant cables to be installed into the post/tower covered by the CPR? Wind turbines are covered by the Machinery Directive, not CPR. Cables for wind turbines can be tested and classified to EN 50575, but not within the CPR framework. Is it allowed to have a classified cable with outer declared diameter of e.g. Ø 5,3 mm ± 1 mm, tested with outer diameter ±5,3 mm so according to one test method and sell it with a diameter of e.g. 4.3 mm ( which normally would have to be tested according to an other test method)? The 10% rule shall be applied Acidity test : Clarify the number of tests If the coefficient of variation epxressed in % is higher than 5, if the values are close to the limit of a class (5%) then two additional tests are carried out, the results for each parameter in these two tests shall be added to the set of results obtained in the minimum number of tests. Next, the two extremes (highest and lowest) for each parameter individually shall be excluded. If the if the values are in the middle of the class then not further test is needed. Is a FOC with more than 2 concentric layers of multi-tubes around a central strengthening member in the same family as a single layer concentric around a strengthening member with increased size using the same plastic as the tubes? As an example, whereupon the units are replaced with solid plastic, then the family is the same as it is noted in the EXAP rule that the bigger problem is tubes with air gaps, not solid material Which mounting arrangements can be made for cables which do not meet the minimum dimensions in EN 50399 (i.e. duplexes) ? E.g. for 5 cables = stack of 5, 2 layers of 2 plus 1 all horizontally orientated, stack of 4 horizontal + 1 vertical on the side, etc. The bundles shall be circular and as close-packed as possible and with an approximate diameter of 10 mm. The spacing between bundles remains at 10 mm. About yearly testing: what does exactly “yearly” mean?
In effect it could be:
A. The solar year
B. 365 days from type testing
C. 365 days from certificate
Usually the date for defining the yearly testing is the date of issuance of the certificate (beginning of CE marking) for AVCP1+. First sampling for audit FPC test would take place 12 months (+/-3 months) after the date of first issuance of the certificate. Can audit test (Every 3 years) be considrerd also as the yearly testing for the manufacturer ? No audit testing and FPC testing are two different testings. Large radiating coaxial cables (leaky feeder cables) with slots in copper screen – different slot patterns – different areas of slots – all are hidden within the jacket, but the slot areas are more prone to fire failure as they expose the foamed polyethylene within. Sometimes the cable has a physical rib to identify the side with the slots, sometimes a coloured stripe, sometimes nothing.
How to deal with that for the definition of families and for the mounting/fixing?
Issues and proposals:
(1) families – if the slot areas are comparable, then slot shape may be ignored, they may be treated as the same cable, and only one example tested;
(2) mounting on the ladder should be with the slots facing towards the burner – this is justified as generally the cable will be mounted with the slots facing into a tunnel area, not facing the wall.