protection of power system saves man, machine, material

1. Protective device
Bhagawan Prasad
Chartered Engineer
amieclub@gmail.com

2. TYPE OF PROTECTIVE DEVICE
 FUSE LOW
VOLTAGE
 FUSE HIGH
VOLTAGE
 MCB
 ELCB
 MCCB
 RCCB
 SFU
 BREAKRS
 RTD
 THERMOCOUP
LE

THEWRMOSTA
TE

3. HT FUSE RATING 11/0.415KV
KVA PRIMARY SECONDR
Y
MIN.
FUSE
MAX.
FUSE
50 2.9 72 6 10
75 4.3 108 10 16
100 5.8 144 16 25
125 7.2 180 16 40
160 9.2 231 16 40
200 11.5 290 25 40
250 14.4 360 32 40
315 18.2 455 40 63
400 23 576 40 63

4. RTD
 MADE OF PLATINUM , NICKEL, COPPER
 TEMP- 600 DEGREE

5. THERMO COUPLE-TEMPERATURE
SENSOR
 MADE –NICKEL, PLATINUM , COPPER
 RATING –UPTO 3000 DEG.

6. BMR
 RATING –a) with CT b) without CT

7. THERMOSTAT
 RATING-5A

8. Relay
 Thermal over load
relay
 Over current relay
 Under voltage relay
 Frequency relay
 Earth fault relay
 Buchholz relay
 Master trip
 Auxiliary relay
 OTI

9. MOTOR PROTECTION UPTO
55KW
 SHORT CIRCUIT
PROTECTION BY
FUSE
 SINGLE PHASING
PROTECTION
 THERMAL OVER
LOAD
 WINDING
TEMPERATURE
PROTECTION

10. MOTOR PROTECTION 55-200
KW
 SHORT CIRCUIT
PROTECTION BY
FUSE
 SINGLE PHASING
PROTECTION
 THERMAL OVER
LOAD
 WINDING
TEMPERATURE
PROTECTION
 STALLED ROTOR

11. PROTECTION OF HT MOTOR
 SHORT CIRCUIT PROTECTION BY
FUSE/BREAKER
 SINGLE PHASING PROTECTION
 THERMAL OVER LOAD
 WINDING TEMPERATURE PROTECTION
 STALLED ROTOR
 UNDER VOLTAGE
 BEARINGOVER TEMPERATURE
 DIFFERENTIAL PROTECTION
 PHASE REVERSAL

12. Transformer rating
 25,40,63,100
 150,250,300,
 400,500,630,750,
 1000,1250,1600,
 2000,2500
 150,250,300,
 400,500,630,750
,
 1000,1250,1600,
 2000,2500
Distribution Power

13. PROTECTION OF DISTRIBUTION
TRANSFORMER
 Over current
protection
 Earth fault
protection
 Buchholz relay
 OTI
 WTI
 Low oil level

14. PROTECTION OF POWER
TRANSFORMER
 Over current protection
 Earth fault protection
 Buchholz relay
 OTI
 WTI
 Low oil level
 Differential protection
 Over fluxing

15. CABLE PROTECTION
O/C +E/F
(CDG31)
Feeder
differential

16. Busbars
 Differential protection (CAG34)

17. Outgoing feeders from 11KV
SWBD
 Differential (HORM-4)
 O/C +E/F (CDAG 51)

18. RESSTRICTED EARTH FAULT
RELAY

19. BIMETALIC =BMR

20. BUCHHOLZ RELAY

21. MASTER TRIP

22. ACT FAST AND INITIATE
FIRST
 बड़ा सोचो
 तेजी से सोचो व
 सबसे पहले सोचो
 िवचारो पर िकसी का
 एकािधकार नही होता.
---- धीरभाई अमबानी

23. THANK YOU