Customer wtness testng gude Ths gude s amed at explanng why we need to wtness test equpment whch s beng connected to our network, what we actually do when we complete ths testng, and what you can do to help ths process run more smoothly. Why do we need to complete Wtness Testng? When an applcaton to connect generaton s receved, desgn work s completed to ensure that the local network can accept the electrcty generated, and contnue to operate wthn the requred legal lmts. The frst prorty when operatng an electrcal dstrbuton network s to ensure that t s operated n a safe manner. However, sometmes the generator or network may operate abnormally causng faults. When ths happens we can t allow the generator to contnue to backfeed a fault and/ or create an sland network whch poses further rsk. Therefore t s essental to ensure loss of mans protecton, where the generator wll automatcally dsconnect protectng staff and assets. Wtness testng s where we, the network operator, attend the ste of your generator to wtness your commssonng engneer test the protecton systems assocated wth your generator and ensure they operate correctly. What do we do when we complete Wtness Testng? We wll attend ste and satsfy ourselves that the equpment meets the requred specfcatons for dsconnectng a generator from the local dstrbuton network n the event of abnormal operaton. There are a number of tests that must be completed, and these can vary dependng on; The sze of the generaton (capacty) The type of the generaton (solar, wnd etc.) The type of equpment beng used (whether t has been type tested) Prevous experence wth an nstaller or a certan type of equpment Prncple Systems A gudance document has been produced by the Energy Networks Assocaton (ENA) whch s called G59/3. Ths document provdes the engneerng recommendatons for connectng generaton. We operate to the requrements of ths document and t s recommended that any nstaller connectng a generator s fully acquanted wth ths document. Under G59/3 the process for wtness testng depends on the nature of the system. The prncple systems are: Type-tested systems (no G59/3 relay requred) Non type-tested systems (G59/3 relay requred) Prncple Systems Short-term parallel systems (G59/3 relay requred) Included below s further gudance whch relates to the three prncple systems hghlghted above;
Customer wtness test gude Type-tested Systems What s a type-tested system? A type tested system s one whch has been approved by the Energy Networks Assocaton (ENA) and for whch they have ssued a certfcate to the manufacturer to confrm conformty of the type tested system requrements. An example of ths would be a 200kW solar PV system usng typetested nverters <50kW. Why do we wtness test? It s our responsblty as a Dstrbuton Network Operator to ensure that generaton connected to our network and the assocated protecton system meets the requrements of G59/3. Labellng s very mportant Dual/mult supply labels The nverter and assocated solators/ Mnature Crcut Breaker (MCB) clearly PV on roof labels (where applcable) DC and AC lve cable labels All solators should be lockable for safety when workng on the generaton system. For type-tested systems we have an approved lst of nstallers. We wll add you to ths lst once we have wtnessed one of your nstallatons to our satsfacton. An approved nstaller n our Southern Electrc area wll be able to wtness test ther own nstallatons up to 500kW. We wll revew ths on a regular bass. Please note that f the generatng system ncludes a devce lmtng export capacty we wll attend n person. We always reserve the rght to wtness test any ste. How do we carry out a wtness test? As a customer you must complete appendx 13.2 of the G59/3 document and comply wth the requrements of G59/3 testng that relate to schematcs and labellng etc. Wtness testng for type-tested systems s based on ths document. As an nstaller t s your responsblty to ensure that G59/3 protecton settngs have been set up on the typetested equpment. Schematcs/sngle lne dagrams and approprate labellng should be dsplayed at both the pont of connecton to the network (whch s often the customer s man board) and the locaton of the nstallaton. The schematc should be relevant to the ste and not smply a typcal system. If the system changes, you should nform SSEN as a further wtness test may be requred and you should also update the schematc dagram at the pont of connecton.
Customer wtness test gude Type-tested Non type-tested Systems Systems What s a non type-tested system? A non type-tested system s one that uses non type-tested factory approved equpment (as defned n G59/3) whch means a G59/3 relay must be used. Some examples of ths would be: A Hydro, Wnd and Solar PV system usng non type-tested nverters wth a G59/3 protecton relay A CHP System An Anaerobc Dgester wth a gas engne A desel engne It s worth notng that sometmes type-tested equpment can be used as part of a non type-tested system and therefore stll requres a wtness test as a G59/3 relay would be n use. Any addtonal equpment n the nstall (e.g. nverter) contanng G59/3 protecton should be set to mrror the settngs appled n the G59/3 relay. Labellng s very mportant Dual/mult supply labels The nverter and assocated solators/ Mnature Crcut Breaker (MCB) clearly PV on roof labels (where applcable) DC and AC lve cable labels All solators should be lockable for safety when workng on the generaton system. Why do we wtness test? It s our responsblty as a Dstrbuton Network Operator to ensure that generaton connected to our network s safe and the assocated protecton system meets the requrements of G59/3. All non type-tested systems need to be wtness tested however ths can be at our dscreton at Low Voltage. How do we carry out a wtness test? Upon acceptance of your quotaton your connectons delvery team wll contact you to arrange the wtness test. An SSEN engneer wll wtness the customers/nstallers apponted commssonng engneer perform the G59/3 test n accordance wth appendx 13.3 of G59/3. In addton further tests wll need to be performed and wtnessed such as: Provng the tmng of the generaton crcut breaker/contactor Dynamc loss of mans response Loss of control/auxlary supply to G59/3 equpment response In addton to the tests specfed above you must complete appendx 13.2 of the G59/3 document and comply wth the requrements of G59/3 testng that relate to schematcs and labellng etc. Schematcs/sngle lne dagrams and approprate labellng should be dsplayed at both the pont of connecton to the network (whch s often the customer s man board) and the locaton of the nstallaton. The schematc should be relevant to the ste and not smply a typcal system. If the system changes, you should nform SSEN as a further wtness test may be requred and you should also update the schematc dagram at the pont of connecton.
Customer wtness test gude Type-tested Non type-tested Systems Systems What s an nfrequent short term parallel system? A short-term parallel system s one that uses non type-tested factory-approved equpment (as defned n secton 7.3 of G59/3). G59/3 states that the system s allowed to run n parallel wth the Network for a maxmum perod of 5 mnutes per calendar month and no more frequently than once a week. A common example of ths s a back-up desel generator system. Why do we wtness test? It s our responsblty as a Dstrbuton Network Operator to ensure that generaton connected to our network s safe and the assocated protecton system meets the requrements of G59/3. Labellng s very mportant Dual/mult supply labels The nverter and assocated solators/ Mnature Crcut Breaker (MCB) clearly PV on roof labels (where applcable) DC and AC lve cable labels All solators should be lockable for safety when workng on the generaton system. All nfrequent short-term parallel non type-tested systems need to be wtness tested however ths can be at our dscreton at Low Voltage. How do we carry out a wtness test? An SSEN Engneer wll wtness the customers/nstallers apponted commssonng engneer perform the G59/3 tests n accordance wth the settngs n secton 10.5.7.2 on page 64 of G59/3. In addton further tests wll need to be performed and wtnessed such as: Prove the tmng of the generaton crcut breaker/contactor Dynamc loss of mans response Loss of control/auxlary supply to G59/3 equpment response Maxmum parallel tmng test In addton to the tests specfed above you must complete appendx 13.2 of the G59/3 document and comply wth the requrements of G59/3 testng that relate to schematcs and labellng etc. Schematcs/sngle lne dagrams and approprate labellng should be dsplayed at both the pont of connecton to the network (whch s often the customer s man board) and the locaton of the nstallaton. The schematc should be relevant to the ste and not smply a typcal system. If the system changes, you should nform SSEN as a further wtness test may be requred and you should also update the schematc dagram at the pont of connecton.
Customer wtness test gude Type-tested How to arrange Systems a wtness test Once your project has been accepted, you wll be contacted by an SSEN Project Manager. Durng ths call, the Project Manager wll arrange a date for your wtness test or f you are not ready the Project Manager wll provde ther contact detals for you to call when you are ready for your Wtness Test to be carred out. Please provde 2-3 weeks notce to your Project Manager when you are ready for your Wtness Test. Should you have any questons please speak wth your Project Manager or contact your Commercal Contract Manager. commercal.contracts@sse.com