1, scope of application
1. 1 This process specification is applicable to the combined assembly of box-type distribution transformers (European transformers) with voltage of 10kV and capacity of 1600kVA or less.
1.2 This specification includes box type, high and low voltage switchgear, transformers, their online configuration and the assembly of other groups of transformers.
2. Equipment and tools
2. 1 Equipment: crane, drilling machine, copper bus processing machine, tin lining furnace, etc.
2.2 Tools: hand electric drill, electric riveting machine, electric wire saw, cold pressing pliers, hammer, square, tape measure, electrician knife, screwdriver, hair dryer, wrench, etc.
3. Materials
Copper bus, wiring nose, cable, insulating tape, etc.
4, process preparation
4. 1 Be familiar with the drawings, technical requirements and process documents assembled according to the production plan.
4.2 Prepare accessories and measuring tools such as high and low voltage cables, copper busbars and wiring noses. According to the drawing requirements.
4.3 Clean up the work site and keep it clean and tidy.
5, electrical assembly process block diagram
6. Process flow
6. 1 Inspection of switchgear
6. 1. 1 Check the configuration and installation dimensions of high and low voltage switchgear one by one according to the drawing requirements, and further improve the imperfections until they meet the drawing requirements.
6. 1.2 The measuring instruments in the low-voltage distribution cabinet must be checked and verified by relevant departments before installation.
6.2 Preparation of Lead Hole
According to the requirements of the drawings, draw the positions of lead holes in the high and low voltage chambers respectively, and carefully saw the square holes with a wire saw. Then prepare aluminum alloy and insulating lead plate.
6.3 Installation of Transformer and Switchgear
6.3. 1 First, carefully remove the top cover of the box, tear off all protective films on the box wall, and check whether the mounting holes of the box base are consistent with those of the transformer and switch cabinet. Then carefully separate the transformer, high voltage cabinet and low voltage cabinet.
Hoist into the corresponding room and lock all bolts.
6.4 Preparation and installation of high and low voltage leads
6.4. 1 Measure the length of the connecting cable from high and low voltage of each phase of the transformer to the switch cabinet according to the actual situation and cut it. Carefully remove the insulation at both ends with an electrician knife. Stripping length shall be as specified in the drawings.
6.4.2 Processing grounding wire. Carefully peel off the PVC sheath and adhesive tape layer at the switch end 150 mm long of each phase of high-voltage cable, and weld the grounding lead at the adhesive tape. Wipe the main insulation with a clean cloth, then fill the concave place with filling glue, finally add stress tube and heat shrinkable tube, and blow the heat shrinkable tube with a hot fan to soften and set.
6.4.3 Crimp the connecting noses at both ends of the high and low voltage cables firmly and reliably with cold crimping pliers, which requires beautiful crimping.
6.4.4 Connect the crimp cables of each phase to the corresponding terminals respectively, and do not connect them wrongly. The connection shall be firm and reliable.
6.4.5 If the low-voltage lead is a copper bus, the copper bus should be punched, bent, tinned and painted according to the measured size. The copper bar requires no burr, no hammer marks and beautiful appearance.
6.5 Connect each grounding wire and lighting system according to the drawing requirements. Grounding resistance shall meet the requirements of technical conditions. The travel switch of lighting should be connected reliably.
6.6 Mount the top cover, carefully inspect the whole product, and send it to the laboratory for electrical test according to the technical conditions after inspection. Finally, put the test data on the nameplate and set it on the box with the signboard.
7. Matters needing attention
7. 1 When lifting transformers and switch cabinets, handle them with care to prevent collision.
7.2 The assembly site must be kept clean, and the ground must be free of water and dust to ensure the product quality.
7.3 After assembly, the tools and measuring tools shall be counted to prevent them from being missed on switchgear and transformers.