Date: August 2011
Company: MLC / Santiago – Metropolitan Region.
The following work was realized to interior mining dry substation:
Low voltage cell
– The low voltage reconditioned cell of the interior mining dry substation is constituted by circuit of control and strength.
– BT board with general reconditioned interrupter, 1200 Amps. Capacity. 70 kA, 400 Volts, and it adjusts to In. Regulation and electronic protections.
– It includes a maximum and minimum voltage relay connected to a firing coil of the general interrupter.
– The control system will be located in 220 Vac, 50 Hz with all its respective protections.
Medium Voltage cell
– The medium voltage reconditioned cell of the dry interior mining substations is constituted by the circuit of control and strength.
– The cell will be equipped with a reconditioned disconnector to operate in low charges, with its corresponding operation mechanism, complying with the design requirements 630 Amperes, according to VDE 0670 norms, class 12 kV.
– Heater resistance-type, inspection window and interior light turtle-type.
– It has ground connection when the disconnector is not closed.
– It has lightning rode of zinc oxide; class 6 kV, 10 kA.
Cabinet
– Reconditioned, fabricated in iron steel CAP KIPS to 37-24. It contains eyebolts to pull and hoist base SKI for dragging.
– In BT cells and MT lateral of dry transformer, frontal doors with a minimum aperture 120o abatement and grounding shots in doors and mounting plaque.
Identification
– Between the junction or energized parts, closer to the protection of the interior edge of the frame of the cabinet, minimum distances will be respected and will allow an easy mounting and cabling.
– For safety, the doors of MT and BT cells and the bars of arrival will land to the ground. All the bars of arrival to interrupters will be protected with shrink sleeves.
– The supplying of the principal interrupter in BT will use, at least, the same section in drivers than the ones that the interrupter possess.
– The door of the MT cell will have a template sight-glass of 4 mm of thickness, to see the position of the connectors.
Inspection and Tests
– Insulation with Megger 5000 volts, continuity of the circuits applying the entrance voltage and measuring the out voltage.
– The routine tests to dry distribution transformers, according to ANSI C-57.12.91.
– Verification of painting quality. Verification of exterior dimensioning of S/E.
– Verification of the out bars numeration, of the colours code in cabling of control and strength, and the correct operation of the three-phase interrupter.
