High voltage for apparatus under Safe Access Rules and statutory regulations is defined as being greater than 1000V ac or 1500V dc.

Transcription

1 Clean, Green & Safe Management System SP Process Authority: HV Test Engineer Peter New High Voltage Testing Approval: EO Engineering & Projects Ken Lister Version Date: 22/02/2012 Revision: A 1. PURPOSE This procedure defines: The High Voltage (HV) Testing authorisation management process, The minimum requirements for planning & undertaking HV tests, and The safe working methods to be used by personnel when performing High Voltage tests on Snowy Hydro s equipment. High voltage for apparatus under Safe Access Rules and statutory regulations is defined as being greater than 1000V ac or 1500V dc. For electrical test safety and authorisation purposes, however, these HV Procedures will also apply when the test equipment is capable of transforming a low voltage test source to High Voltage (greater than 1000Vac) or of supplying or storing electrical charge able to produce an electrical shock current. This definition includes winding resistance measurement on high voltage generators and power transformers rated greater than 500kVA. 2. SCOPE This procedure will be applied to define the specific experience, training, and competency required by employees who undertake High Voltage testing of Snowy Hydro s electrical equipment. It describes the accountabilities of all parties involved in HV testing, and the various authorisation levels and their definitions. It also describes the minimum test planning, documentation, and approvals process for HV testing. This document must be read in conjunction with SAP - 15 Permit Preparation, Issue and Control, which describes the process for preparation, issue, and control of permits. Figure 1, below, demonstrates the processes governed by this procedure, and by SAP 15. SP24-76: Rev A THIS DOCUMENT IS UNCONTROLLED IN HARD COPY Page 1 of 9

2 2.1 Process Flow AFA Permit Issue Permit Area Safety Requirements Confirm Authorisation SAP 15 Permit Preparation, Issue and Control Ellipse Work Order Test required Equipment Due Date High Voltage Test Officer Authorisation High Voltage Test Procedures Technical requirements of the test Test equipment Hazards of the test Hazard Assessment Test hazards Site Hazards Work Method Statement Job steps Step Hazards Control ID HV Testing Hazard Controls Barriers Signage Procedures Undertake High Voltage Tests Routine Maintenance Commissioning Ad-hoc request Equipment details: Location Specificat ions Site specific hazards SP24-76 High Voltage Testing High Voltage Testing model 16/08/2010 Figure 1 3. AUTHORISATION AND ENDORSEMENTS To become HV test authorised, an employee must: i. be assessed as competent and authorised to Safe Access Rules level C3. ii. have the prerequisite experience, as described in the High Voltage Testing Officer Development Path, Appendix 1 iii. be assessed as competent by the High Voltage Test Engineer (HVTE) for the respective HV Authorisation category. 3.1 Authorisation Categories The HV authorisation codes are: H0 H1 H2 authorised to work in HV test team, but not authorised to be a HVTO. HVTO authorised to receive a HV Test Permit for HV Insulation Resistance and winding resistance measurement. HVTO authorised to receive a HV Test Permit for all types of HV testing. These HV endorsements are managed, issued and rescinded by the HV Test Engineer, and are to be shown on the Authorisation Database 3.2 Test Set Competency Categories SP24-76: Rev A THIS DOCUMENT IS UNCONTROLLED IN HARD COPY Page 2 of 9

3 For H2 authorisation an additional endorsement is required by the HVTE to allow the HVTO to operate particular test sets. The test set competencies include but are not limited to: Doble M4000 Schering Bridge Bauer 55kV AC test set Ferranti 35kV AC test set Ferranti 50kV test set Hansom 25 kv test set Test set competency endorsements are: T for In training C for competent to operate A for authorised to train and assess A person endorsed as T for a particular test works under guidance of a person classed as A or C until the A recommends for them to be assessed by the HVTE. A person endorsed as C for a particular test must be recommended by an A to be assessed by the HVTE to move from C to A. A H0 authorised person cannot be endorsed to operate test sets. C endorsement for winding resistance and insulation resistance test sets can be attained by completing an i-learn online assessment and a practical assessment by the HVTE. These Test Set Competency endorsements will be managed, issued and rescinded by the HV Test Engineer, and are to be shown on the Authorisation Database. Maintaining an HV authorisation will require 3-yearly re-assessment by the HVTE. The assessment will consist of: H0 training and assessment on this procedure H1 training and assessment on this procedure, plus training and assessment on IR and winding resistance testing H2 training and assessment on this procedure, plus evidence of testing undertaken 3.3 Contractor authorisation & endorsement. Contractors must comply with Snowy Hydro s procedures whenever engaged on Snowy Hydro premises. For HV Testing in operational areas, this may be achieved by either working under direct supervision of Snowy Hydro HV authorised recipient authorised to the appropriate level according to this procedure or by the contractor recipient being HV authorised according to this procedure. In the case that the contractor is not authorised to Snowy Hydro procedures, then the contractor must have current high voltage authorisation issued by an energy authority or the contractor s employer and be competent in performing the proposed test. Contractor authorisation and credentials must be accepted and endorsed in writing by the HVTE. SP24-76: Rev A THIS DOCUMENT IS UNCONTROLLED IN HARD COPY Page 3 of 9

4 Contractors testing exclusively in non operational areas may be HV authorised without needing to be authorised to Snowy Hydro s Safe Access Rules with the approval of the HV Test Engineer. 4. HIGH VOLTAGE TESTING 4.1 Testing in Operational and Non Operational Areas This Procedure will be applied for all high voltage testing in operational and non-operational areas. The normal Application for Access process applies for all high voltage testing in operational areas. For HV testing in all other areas, notification and agreement must be obtained from the manager responsible for the site, so that the testing can be coordinated with other work in the area, and to ensure local personnel are aware of the tests. 4.2 Planning of High Voltage Tests In preparing for a HV Test on a particular item of electrical apparatus, the following points need to be satisfied by the HV Test Officer: ensure that the appropriate test equipment is available and serviceable - check the ratings identify all the test object conductors and the means of isolating those not to remain earthed - Operating Diagrams may be used to identify system switching, isolation and operational earth locations connected to the test object HV conductors determine where test earths under control of HVTO are required plan layout of the test equipment and barriers and connections to test object define the HV test working area for permit purposes and obtain agreement for the use of the test area in non-operational areas. Obtain agreement for the desired test team members. For non-snowy Hydro authorised personnel written approval must be granted by the HVTE. Submit an Application for Access (AFA) describing the specific requirements of the job (When testing in Operational Areas only). Document the risk assessment and work method steps in a work method statement (WMS) that complies with Snowy Hydro Clean Green & Safe procedures. SP24-76: Rev A THIS DOCUMENT IS UNCONTROLLED IN HARD COPY Page 4 of 9

5 Document the Test Procedure (TP). Obtain the most recent past test report for comparison if applicable. 4.3 Hazard Assessment and Work Method Statements A Hazard Assessment must be conducted during the planning phase of the test, in order to develop the High Voltage Test Work Method Statement, in accordance with QP25-16: Operational Risk Management. The person who conducts the Hazard Assessment and/or develops the Work Method Statement must be suitably qualified and familiar with the test equipment to be used and the apparatus to be tested. The Work Method Statement must be approved by the HV Test Engineer 4.4 Test Procedures An approved Test Procedure (TP) must be used for all HV tests. The TP must be approved by the HV Test Engineer (HVTE). The TP must include the following components: Prerequisites for testing Sequential test steps Acceptable test results Method of recording data from the tests Emergency safety procedures in the event of safety controls failure. 4.5 Testing Area Where HV testing is conducted under a Test Permit (ie in Operational Areas), the permit area will be defined with black/yellow barriers as per SAP-23. In all cases, the HV test area will be demarcated by Red & White HV test barriers, placed in appropriate positions that ensure minimum approach distances (MAD) are maintained. While the test circuit is energized a chain barrier that maintains MAD is to be placed between the tester and the test object. The arrangement of the HV test barrier is the responsibility of the HV Test Officer. There should be only one entrance to the test area. Signage indicating Danger - High Voltage Testing In Progress will be placed at the entrance and at intervals around the HV test perimeter whilst the tests are in progress. When tests are being set up the sign at the permit entrance will be substituted for a Warning-Under Permit sign. SP24-76: Rev A THIS DOCUMENT IS UNCONTROLLED IN HARD COPY Page 5 of 9

6 All movements within, into and out of the HV test area are strictly under the control of the HVTO when the Danger - High Voltage Testing In Progress is displayed (Note Where the apparatus being tested spans a number of different levels within a multilevel operational area or over several areas within an operational area, each area to be accessed may be separately barriered as aforementioned) Where the permit area extends beyond the sight of the HVTO operating the test equipment, the HVTO will post a safety observer outside the test area at this / these point(s). The function of this person is to prevent access to the test area during testing and to warn the HVTO of any unexpected consequences of the test. 4.6 Access to the HV test Area In addition to normal requirements to gain access to the test area the following will apply: only personnel authorised to a minimum of H1, are permitted to receive a HV testing Permit Only personnel authorised to H0 are permitted to sign onto a HV testing permit In addition, required personnel may be granted permission to access the test area after the HV test officer has completed the following: (a) Checked appropriate Safe Access Rules authorisation (b) Carefully explained the hazards and controls described in the Work Method Statement with the person, and had them sign onto it (c) Provided direct and continuous supervision of the person by HVTO or another H1 authorised (or higher) person. normal access to the test area will only occur when the Warning - Under Permit sign is displayed at the permit entrance; prior to being signed onto the permit, the work party must be checked by the HVTO to ensure that they: o o o o are totally conversant with the procedures to be used in case of an emergency; are aware of the test procedure and the voltage to be applied and the minimum approach distance to be used; are aware of when they can enter the test area and the safe zones within the test area; and are informed they must sign-off whenever leaving the test area. 4.7 Earths and Connection of Test Equipment A test circuit conductor is only in a safe-to-hold condition when an earth is attached at the same point. The conductor rating must be SP24-76: Rev A THIS DOCUMENT IS UNCONTROLLED IN HARD COPY Page 6 of 9

7 sufficient for a short-circuit on the HV side of the test power supply. A conductor making this type of connection is called a test earth. When the system HV power supply is used to energise the test object then only operational earths applied by an authorised competent operator may be used. Operator applied earths will be Warning tagged to indicate who can remove / apply them during testing. Whenever the permit isolation has been changed during testing, it is necessary to prove the electrical circuit is de-energised before replacing the operational earths. 4.8 High Voltage Insulation Resistance and Winding Resistance Testing Insulation resistance tests in operational areas where the test instrument is used to apply above 1000V AC or 1500V DC or winding resistance testing where the test is on apparatus capable of creating or storing dangerous charges, are done under a Testing Permit marked High Voltage. 4.9 Performing the Test High Voltage testing can only be done when there are two people who hold current CPR certificates (Note In Victoria this must be a First Aid Certificate) present that are familiar with the test procedures and emergency procedures. This requirement will only be waived with the written approval of the Executive Officer Engineering & Projects. Prior to testing, the sign at the test entrance will be substituted with a Danger - High Voltage Testing In Progress sign and Red/White HV test barrier will be placed across the entrance. (Note Where the apparatus being tested spans a number of different levels within a multilevel operational area or over several areas within an operational area, each barrier will be closed as aforementioned) Once this is done no one may enter the permit area. Where necessary Safety Observers must be posted. Prior to the test, all non-essential personnel must be removed from the test area. Only personnel essential to the function of the test will be permitted to remain in the test area during the testing. Additionally, prior to commencing the test, the HVTO must inform each work party member of the test procedures and their duties, and confirm their understanding of this information. The HVTO is responsible for all personnel within the test area. All persons in the test area must obey all reasonable instructions given by the HVTO. Immediately prior to commencing tests, the HVTO must advise the testing team that HV is about to be applied, and notify them when the test supply voltage is down, off, and earthed. Once the test is concluded the HVTO will restore the entry to the test area and advise the work party when they can approach the apparatus. Where testing requires that one or more earth(s) to be temporarily SP24-76: Rev A THIS DOCUMENT IS UNCONTROLLED IN HARD COPY Page 7 of 9

8 removed, the electrical apparatus must be regarded as being alive, irrespective of whether or not the testing voltages have been applied. At the conclusion of the test, ensure any electrical apparatus under test that has become electrically charged during testing is fully discharged and left in a safe condition. All earths that were temporarily removed to allow the electrical testing to be carried out should be reapplied immediately; All earths that are required to remain in situ for a prescribed period of time at the completion of the tests will be noted on the HV test permit, along with the duration required Results of Tests Results from the test will be recorded and filed in a manner prescribed by the High Voltage Test Engineer. 5. ACCOUNTABILITIES Technical Specialists Determine HV testing requirements for assets under their specialisation. Ensure the requirements are identified as Critical Maintenance Requirements in the Ellipse Job Procedures. Ensure appropriate task frequencies, equipment associations, responsible work groups, and linked documents are identified. Review HV test results. Review HV testing work order compliance High Voltage Test Engineer (HVTE) Approve HV test procedures. Approve HV Work Method Statements. Manage H level authorisation endorsements. Select appropriate HV test equipment. Develop HV competency assessments. Approve HV competency training program High Voltage Testing Officers (HVTO) - Plan HV tests in accordance with this procedure. Recieve HV Test Permits in accordance with this procedure, relevant SARs & SAPs, HV procedures, and Work Method Statements. Executive Officer E&P Approve nomination of High Voltage Test Engineer 6. ATTACHMENTS Appendix 1 - High Voltage Testing Officer Development Path SP24-76: Rev A THIS DOCUMENT IS UNCONTROLLED IN HARD COPY Page 8 of 9

9 APPENDIX 1 - High Voltage Testing Officer Development Path Position Apprentice - Electrician Minimum Qualification Secondary Education (eg HSC) MinSAR authorisation Min HV Testing authorisation Max HV testing authorisation Experience Key Tasks PARTICIPATE in electrical maintenance, installation and commissioning under direct supervision PARTICIPATE in Insulation Resistance & Winding Resistance testing under direct supervision, when H0 authorised. C3 Nil H0 Nil Tradesperson Electrician (C3 authorised) Cert III Electrical engineering (trade) C3 H0 H1 indentured apprenticeship LEAD and UNDERTAKE electrical maintenance, installation, and commissioning PARTICIPATE in protection maintenance, installation, and commissioning UNDERTAKE Insulation Resistance & Winding Resistance testing Specialist Trade Protection Tradesperson Electrician (R authorised) Cert III Electrical engineering (trade) R H0 H2 2 years post-trade 12 months participating in protection maintenance, installation, and commissioning LEAD and UNDERTAKE electrical maintenance, installation, and commissiining (electrician) UNDERTAKE protection maintenance, installation, and commissioning (specialist trade) UNDERTAKE Insulation Resistance & Winding Resistance testing PARTICIPATE in HV testing >1kV under direct supervision Technical Officer - Protection Diploma Electrical Engineering R H0 H2 3 years post-trade 12 months undertaking protection maintenance, installation, and commissioning 12 months participating in HV testing LEAD and UNDERTAKE electrical maintenance, installation, and commissioning LEAD and UNDERTAKE protection maintenance, installation, and commissioning LEAD and UNDERTAKE HV testing within authorisation endorsement PARTICIPATE in HV testing outside authorisation endorsement Technical Officer - Protection and Testing Diploma Electrical Engineering R H2 H2 4 years post-trade 12 months leading protection maintenance, installation, and commissioning 12 months leading HV testing <2.5kV or participating in HV testing >2.5kV LEAD and UNDERTAKE electrical maintenance, installation, and commissioning LEAD and UNDERTAKE protection maintenance, installation, and commissioning LEAD and UNDERTAKE HV testing any voltage, any test SP24-76: Rev A THIS DOCUMENT IS UNCONTROLLED IN HARD COPY Page 9 of 9