TECHNICAL SPECIFICATION FOR LOW TENSION (FIXED) SHUNT CAPACITOR UNITS (MPP TYPE) FOR DISTRIBUTION TRANSFORMERS Spec. No. MSEDCL/Dist:MSC-III/ LT MPP CAP/11/2009/R0
B. HOUSING ASSEMBLY:
Where more than one units are used these individual units should be housed in metallic enclosure (square type) made of minimum 2 mm thick CRCA sheet with proper ventilation and with front-hinged door to enable the easy maintenance and replacement in case of damage of any units. Only three terminals shall be brought to the individual MCB of suitable ratings, which are clamped in the enclosure on the back sheet. There should be provision for cable entry.
The outside of the enclosure should have smooth and tidy look and shall be coated with weather proof & corrosion resistant paint of dark admiral grey shade. There should be proper provision for clamping so as to mount the metallic enclosure on the transformer pole structure. Copy of GA drawing is enclosed for reference. Proper cable glands wherever necessary should be provided. The maximum length of the cable required shall be 5 mtrs/ Installation & the same shall be supplied by the supplier. Lugs of proper size shall be crimped to the cable.
TP type MCBs being provided shall be of appropriate rating as per the rating of the capacitor. The MCBs shall be suitable for capacitor switching duty (‘D’ Curve ) & shall conform to IS:8828/1995 / IEC: 60898. Approved make of MCB’s shall be Siemens / Havells / Schnieder / Hagger (L&T) / Indo Asian etc. Type test for MCB shall be submitted before supply. Interconnection wire between capacitor to MCB shall be of flexible copper wire of suitable size.
The typical rating of MCB and PVC Cable are as given below
Rating of MCB
Connection between MCB to
63 Amps,3P, 10KA MCB (‘D’ Curve) 63 Amps,3P, 10KA MCB (‘D’ Curve)
between capacitor to MCB 10 SQ. MM, Copper ,
FR Grade wire marked)
10 SQ. MM, Copper ,
FR Grade marked)
16 Sq. mm PVC insulated,
Unarmored Aluminum . 3 core, Cable (ISI marked) 25 Sq. mm PVC insulated, Unarmored Aluminum . 3 core, Cable (ISI marked)
Ceramic /porcelain or FRP fiberglass to ensure good insulation with threaded M.S Tin terminals are to be provided. Also to provide copper cable of length 5 metres, 16 sq.mm for connections.
The following information shall be marked indelibly, either directly or by means of a plate, on each capacitor unit in accordance with clause 10.1 of IS: 13340/1993.
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Seal and Signature of Tenderer