what is difference between differential protection and
distance protection and how we calculate the sloop?
Answer Posted / mohanraj
Differential protection is a unit protection, relay works
on the principle of Kirchoff's current Law.
Measuring element is Current Transformer.
The differential current measured between the incoming
current and Outgoing current must be negligible current
during stable and through fault condition. In case of
inzone fault or unstable condition (due to CT saturate)
relay will sense the differential current and issue the
trip signal.
Application: Transformer, Generator and Cable Protection.
**********************************************************
Distance protection is widely used in the transmission
network, its also called impedance protection because relay
operates with respect to fault impedance of the
transmission line. (Z=V/I)
Measuring element is Current Transformer and Voltage
Transformer.
Usually relay having 4 zones of the transmission line.
Zone1,Zone2,Zone3 will be forward zones (Towards the Line)
and zone 4 will be Reverse zone (Towards the Source).
| Is This Answer Correct ? | 51 Yes | 1 No |
Post New Answer View All Answers
A d.c. Shunt motor is found suitable to drive fans because they require?
what is the main difference between power devices and signal devices
what is the acceptable value of TAN DELTA and dissipation factor for 11kV, 1.75HP Motor?.
If we need 4c× 50mm sq cable but it's not available so we can pull 4c×25mm sq two cables?
What is the previous name of Cox's Bazar
HOW TO CALCULATE HV TEST VOLTAGE FOR ELECTRICAL EQPT.
What effect does a very low impedance have on the Voltage regulation? On the short-circuit current?
what is sevice settings for mccb?How can be it setted?
What is current divider rule (cdr)?
wheather the size of windings in motor and generator are the same
write down the formula of cable size in RM if current is 50Amp.
ASTM D 3455 - Standard Test Methods for Compatibility of Construction Material with Electrical Insulating Oil of Petroleum Origin has been used for Testing Transformer Oils with a product placed in it. Aged Control Oil has a Power Factor of 0.032% at 100°C. Aged Oil with a Test component has a Power Factor of 0.093% at 100°. Is this increase acceptable? If not why? How much increase is acceptable?
What is the method for testing the differential protection stabilty in generator? When the time of starting What will happen if differentail protection connection wrong means?
a starter used for squirrel cage induction motor?
Explain M Var? Which types of problem occurs when reactive power increase at the time of full load of plant and at the time of synchronize of plant?