HV EARTHING AND SHORT CIRCUIT LANCE DEVICE For use on maintenance operation and reparation of system parts electrically insulated of interconnection station of hv with air insulation: on coloumn support having top insulator string, on ammmeter transformer, on bar vertical disconnecting switch and on line horizontal disconnecting switch. In accordance to TERNA SPA technical specification: ING. LANCE 01 Rev. 03 of 23/05/2011 In accordance to: CEI EN 61219 RAILWAYS 19 - Railways
GENERALITY Lance equipment are devices for earthing and short circuiting for system parts electrically insulated f interconnection HV station having air insulation. System configuration: 1 A lance device is composed by: 1) n 1 Lance contact for conductor 2) n 1 Earthing and short circuit lance 3) n 1 Flag for signalling of earth connected 4) n 1 Lance contact at ground potential 5) n 1 Metallic extension (optional) 6) n 1 Pole mechanical fixing 7) n 1 Manoeuvring insulating stick 1 2 3 6 5 4 2 5 6 7 4 3 7 Fig.1 Setup of a lance earthing and short circuiting device. USE AND SAFETY ADVANTAGES Earth and short circuit with lances is suited in case of: high short circuit current requiring heavy portable devices with big earthing conductors; qneed of placement of more single phase short circuit devices (in parallel); avoid the danger coming from strong and quick electrodynamic movement of the earthing cable during the short circuit; few space in the substation, limiting the operation capability. 20 - Railways
ECONOMIC ADVANTAGES Earth and short circuit operation with lance offers several advantages, such as: reduction on more than 60% of the operation times; just one operator is able to perform installation of the lance system, without any stress; capability to make the earthing and short circuiting operation on different weather conditions and visibility; absence of maintenance costs as comparison to common portable devices. PRESCRIPTION Lance devices must be used only for the earthing and short circuit of part of systems previously disconnected and after the check of voltage absence. The devices are indicated for a discontinuous use and they have to be changed after the short circuit event. INSTALLATION AND USE SYSTEM INSTALLATION On HV conductor, the LANCE CONTACT FOR CONDUCTOR (A) has to be fixed on the line to put on earth. Then, on the metallic support column, at a height more than or equal to 2m from floor, the two half-jaws of '' ANCHORAGE MECHANIC SUPPORT TUBE "(B) must be fixed by tightening the nuts on the ends of the four bolts M12. Prior to installation of the "LANCE CONTACT AT GROUND POTENTIAL" (D), please consider the need to place a metallic extension (C) between the anchor and lance contact, in such a way to let possible the installation of lances in all possible situations. Then, please adjust the position of the "LANCE CONTACT AT GROUND POTENTIAL" (Fig. D), fixing it by tightening with a force of about 18Nm. The equipped copper cables provided with the lance contact (or metallic extension if any), shall be connected between the split sleeve of the contact lance and the two M12 connections (E) to secure the earthing of mechanical assembly. Lance contact at ground potential assembled in this way is then ready. Now, the lance can be taken, gripping it indifferently in the most convenient way for the operator, in order to insert the contact clamp inside the gap in the sleeve of the contact lance at ground potential. In this way, the weight of the lance is downloaded on the sleeve to your boat and it's possible to maneuver the device from the insulated handle (under the hand guard), slipping and rotating until the potential contact has been reached. When all the components have been installed of the system, please verify the correct whole axial position of the parts. Finally, proceed to the execution of the earthing and shortcircuit holding the device launches in the handle and screw it counterclockwise. The torque limiter will intervene to achieve a tightening torque of 18 Nm ±10 %, more than sufficient to guarantee the proper values are exceeded short circuit provided. A E D B C F Fig.2 Sizes of lance and components and installation diagram RAILWAYS 21 - Railways
LANCE DEVICE COMPONENTS LANCE TERNA certification extended for conductive rod length up to 5450 mm. LANCE TECHNICAL DATA NOMINAL VOLTAGE OPERATING TEMPERATURE: - 25 C 55 C Icc HANDLE LENGTH 0,5 s (L) LENGTH INSULATING SECTION (LL) LENGTH ACTIVE SECTION (LA) TOT. LENGTH (LT MM) WEIGHT 145 170 kv 40 ka 500 mm 750 mm 2450 mm 3700 mm 10 kg 245 kv 50 ka 500 mm 750 mm 3250 mm 4500 mm 12 kg 420 kv 63 ka 500 mm 750 mm 4450 mm 5700 mm 14,5 kg 22 - Railways
EARTHING AND SHORT CIRCUIT LANCE DEVICE Devices composed of an active part in aluminium and stainless steel and having at one end a phase clamp with jaw and retractable tightening screw. At the other end, there is a quick joint of insulating material containing a torque limiter suitable in order to obtain a secure final tightening of the device on the conductor and in this way it can withstand the related event of short-circuit current. The other component of the lance is formed by an insulating rod in epoxy resin to glass fibres with bottom buffer, handle limit and rubber grip; it can be jointed coupling. LANCE CONTACTS FOR CONDUCTORS Contacts for fixed HV conductors single, plied, in threes, tubular ø 36, ø 41.1 and ø 100. Made of aluminium alloy for strong currents: are equipped with tightening bolts made of stainless steel. Application: a) for single conductor on cable all. ø 36 mm for single conductor on cable all. ø 41,1 mm b) for conductor twin on cable all. 36 mm for conductor twin on cable all. 41,1 mm c) for conductor laced on cable all. ø 36 mm d) for aluminium tubolar conductor ø 100 mm a b RAILWAYS c d LANCE CONTACT AT ZERO POTENTIAL Device in aluminium alloy and stainless steel, it's mounted on the mechanical fixing on pole to the aim of receive the lance. It allows for the rotation and translation to reach the contact of a phase potential and connects the lance to earth. Application: e) for systems at 420 kv, 245 kv, 145 kv/170 kv e 23 - Railways
MECHANICAL FIXING AT POLE Jaws in galvanized steel, they are installed on metal poles / grounded structures HV by means of steel screws. Application: f1) for tube support ø 219,1 mm (support ballard 145/420 kv) f2) for tube support e ø 273 mm (on bar vertical disconnecting switch and on horizontal disconnecting line switch 420 kv) f METALLIC EXTENSIONS g) Supports in hot galvanized steel to be installed (if necessary) between mechanical fixing on pole and the contact lance at ground potential, in order to obtain a good alignment of all components of the system of earthing and short-circuiting. Available lengths : 150 mm, 250 mm, 300 mm, 350 mm. g CART MOVED BY HAND FOR THE TRANSPORT OF 10 WITH LANCE ELEMENT OF ENGAGEMENT FOR TOWING POWERED h) Cart in hot galvanized steel with extendible frame; it's able to carry all kinds of lances. h 24 - Railways