NATIONAL ALUMINIUM COMPANY LIMITED - Rites

** Copper flat of equivalent size can be used instead of aluminium flat.
NOTES : Overload relay shall be selected based on actual full load current and starting time.
GENERAL TECHNICAL PARTICULARS OF MCC
GENERAL
1. System
: 415V, 3 phase, 4 wire, 50 Hz. Solidly earthed neutral
2. Type
: Indoor type, cubicle construction, free standing
3. Pollution degree : 4
4. Creepage distance : As per IS-13947 (1993), Part-I
5. Enclosure
: IP54
6. Mounting
: I/C & B/C in single tier and O/G in multi-tier tier arrangement
execution
7. Neutral earthing : Effectively earthed
8. Control supply : 240V AC / 220 DC for ACB
9. Short time rating : 50 kA for 1 sec
10. Autochangeover required? :Yes
11. Delay drop off required? uired? :Yes
12. Control supply
AIR CIRCUIT BREAKER
: 220 V DC for ACB, 240V AC/220 DC for spring charge motor and
240 V AC for MCCB, etc.
1. Service
2. Type
3. Insulation level : 6 kV (1.2x50 micro Sec) Impulse withsta
4. Utilization Category
5. Operating mechanism
I. Closing
II. Opening
III. Latching
6. Auxiliary Voltage
I. Closing
II. Tripping
CURRENT TRANSFORMERS
1. Type
: Resin cast, window type
2. Rated voltage : 415 V +10%
3. C.T. secondary
4. Accuracy
: 1 Amp rating
i. Protection : 5P10 or better for protection
ii. Metering : Class - 1
Technical Specification:Sec-6, Electrical
: Indoor
: Air – break
: 6 kV (1.2x50 micro Sec) Impulse withstand
: B
: Stored energy type
: Motor wound spring operated
: Shunt trip coil
: Mechanically and electrically trip free arrangement
: DC (85% - 110%)
: DC (70% - 110%)
III. Spring charging : 240V + 10% AC or DC motor
IV. Space heater & Lamp : 240V + 10% AC 50 Hz
7. No. of poles of C.B : 3
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