Electroinsulating Footwear and Overboots for Live Working Practical Experience and Evolution of Standards

Transcription

1 Electroinsulating Footwear and Overboots for Live Working Practical Experience and Evolution of Standards Marek Łoboda, Bogumił Dudek Polish Committee of Standardization TC 72 Equipment for Live Working Poland 1

2 Historical Remarks on Use of Electrical Insulating Footwear in Poland General Requirements for Electrical Insulating Footwear according to EN ed.1 Chronology of CLC TC 78 Works on New Requirements for Electrical Insulating Footwear and Overboots General New Requirements for Footwear and Overboots in pren :2017 Summary and Conclusions Outline

3 Historical remarks on use of electrical insulating footwear in Poland The first stable regulations in Poland related to Safe Maintenance of Power Plant Equipment and Substations were introduced in The use of overboots was mandatory when performing i.e. live dust removal from substation equipment, switching operations, etc. The earliest applications of electroinsulating equipment in Poland: a) checking the presence of voltage, b) handling the switch; 1 - voltage detector, 2- electroinsulating platform, 3 - electroinsulating gloves, 4 - electroinsulating footwear, 5 - electroinsulating matting. Source: E. Musiał, Poland

4 Historical remarks on use of electrical insulating footwear in Poland The need of electrical insulating footwear use fo life working Possibility of step and/or touch voltages occurance when live working. Source: Chabin S., Toussaint M.: PPE Directive and Live Working footwear, ICOLIM 2014

5 Historical remarks on use of electrical insulating footwear in Poland Next editions of Polish regulations related to live working procedures were edited in 70thies and 90thies electrical insulating overboots were mandatory as protective equipment at low and medium voltage substations. In 1977 was developed the Polish national standard for electrical insulating footwear and overboots. Two classes were recognized 15 kv and 20 kv and maximum values of leakage currents for proof test voltages were defined as mandatory in routine and periodical control tests. After the accession of Poland to the UE in EN was incorporated to Polish Norms.

6 General requirements for electrical insulating footwear according to EN ed.1 EN 50321:1999 is applicable to footwear for working live or close to live parts of a.c. low voltage installations only, not exceeding 1 kv and classifies footwear as follows : Class 00 for installations with nominal voltage up to 500 V (proof test voltage 2,5 kv and withstand voltage 5 kv), Class 0 for installations with nominal voltage up to 1000 V (proof test voltage 5 kv and withstand voltage 10 kv), Four types of footwear design Two types of overboots design Source: EN and Chabin S., Toussaint M.: PPE Directive and Live Working footwear, ICOLIM 2014

7 Chronology of CLC TC 78 Works on New Requirements for Electrical Insulating Footwear and Overboots In 2012 the CLC TC 78 initiated the new work item related to electrical insulating footwear and overshoes for live working proposed by the UK National Committee, In May 2012 at the CLC TC78 plenary meeting in Brussels the UK NC proposal received 8 positive votes, 1 negative and 1 abstention, New working group WG 5 was created under the convenership of Mr. Adrian Thorp (UK). NCs delegated 9 members to WG5 which represented UK, FR, IT, DE and PL and also the CLC Personal Protective Equipment consultant Mr. Bahima was engaged.

8 Chronology of CLC TC 78 Works on New Requirements for Electrical Insulating Footwear and Overboots The WG 5 TC 78 CLC proposed to elaborate new standards: Live Working Footwear for Electrical Protection Part 1 - Insulating Footwear and Overboots EN , - for footwear where primary protection is against electrical hazards. Live Working Footwear for Electrical Protection Part 2 - Electrical Shock Resistant Footwear and Overboots EN , for footwear for secondary protection against step voltage where the outer sole is tested, only, Live Working Footwear for Electrical Protection Part 3 - Conductive Footwear EN for conductive footwear used in live working. It was decided to start work on Parts 2 and 3 of EN50321 after the completion of Part 1.

9 Chronology of CLC TC 78 Works on New Requirements for Electrical Insulating Footwear and Overboots WG5 met few times in 2012 and 2013 and completed pren CD which was submitted to CENELEC enquiry and received positive vote to proceed to final voting (FV). In December 2014 final CD of pren was submitted to TC 78 Secretary for formal voting with the deadline resulting in failed to achieve majority in FV. The second draft of pren was proposed by WG 5 convener in which scope was included the DC testing up to V d.c. Next was started discussion on a second FV and was decided to distribute a questionnaire document if the second revised draft will be present for second voting.

10 Chronology of CLC TC 78 Works on New Requirements for Electrical Insulating Footwear and Overboots The assessment from PPE consultant was negative with the inclusion to the draft reference to EN being the major reason of non-conformance with PPE Directive. At the TC78 CLC meeting in Brussels in October 2016 was taken the decision related to further proceeding of pren The PPE Consultant did not support that the (F)prEN when ratified, is submitted as a harmonized standard for publication of its reference in the OJEU under the Directive/Regulation and standardization request under which he has assessed it. In March 2017 the CLC TC78/WG5 convenor after a period of activity and consultation with the PPE consultant and CCMC has submitted the draft of EN for FV to the TC secretary. This will follow the process of translation into French and German, then submitted to the NC s for voting.

11 New Requirements for Footwear and Overboots in (F) pren The general changes and modifications introduced to new draft of EN with regards to EN 50321:1999: the addition of electrical classifications 1,2,3 and 4 for a.c. voltages and d.c. proof voltage testing for Class 00,0, 1 and 2, the addition of mechanical Class II according to ISO 2345, 2346,2347, definition of overboot and its style, 16 h moisture conditioning in water for type test, steel balls to be used as inner electrodes for routine test (having completed the production phase) only revised marking test method and marking test, inclusion of test on footwear with penetration resistant insert, inclusion of the test report.

12 New Requirements for Footwear and Overboots in (F) pren Proof test voltage, proof test current and withstand test voltage for footwear Class of foot wear AC Proof test voltage kv r.m.s AC Proof test current ma r.m.s Design (EN ISO 20345/EN ISO A B C D AC With stand test volt age DC Proof volt age ave rage kv kv r.m.s 00 2,5 1 1, , N/a N/a N/a N/a N/a N/a N/a 4 40 N/a N/a N/a N/a not applicable

13 New Requirements for Footwear and Overboots in (F) pren Proof test voltage, proof test current and withstand test voltage for overboots Class of foot wear AC Proof test voltage kv r.m.s AC Proof test current ma r.m.s Design A B C D AC With stand test volt age DC Proof volt age ave rage kv kv r.m.s 00 2, N/a N/a N/a N/a N/a N/a N/a 4 40 N/a N/a N/a N/a not applicable

14 New Requirements for Footwear and Overboots in (F) pren Arrangement for AC electrical tests: a) typical for one tested item, b) picture of arrangement for multiple item testing.

15 Summary and Conclusions Revision of existing standard for electrically insulating footwear for work on low voltage installations was the need resulting from currently used and developing live working technologies in Europe. The Polish NC strongly supported the UK NC proposal for updating the existing version of EN 50321: However, the task for WG5 of proposing the new edition of EN was not easy to be done and the successive drafts of standard were thoroughly discussed and did not reach the final acceptance for almost 5 years (sic!). Also in the last version of draft (F) proposed by WG5 TC 81 CLC convenor are still some technical problems, which require additional discussion or even some additional electrical tests performed in different independent laboratories.

16 Summary and Conclusions According to PL NC experts in the final version of EN : 2017 should be agreed the following issues: to define polarity of d.c. testing voltage used for proof and withstand (?) tests; to consider if the same values of leakage currents shall be required for a.c. and d.c. proof voltage tests (i.e. based on new test results for the same products before and after conditioning in water), to assess if for type tests (after conditioning in water) and routine tests (without conditioning in water) shall be the same values of leakage currents for proof voltage tests accepted, to decide if the footwear and overboots with water absorbing inner lining may pass the required electrical type test if water will be the inner electrode as actually required.

17 Thank You Attention!