Answer / raghavendran

Checking of the pickup and dropout value

When checking the pickup value, the analogue input signals
of the single phase alternating test current have to be fed
to the relay via terminals.When testing the pickup value,
the alternating test current must first be lower than the
set pickup value.
Then the current will be increased until the relay picks up.
The value that can be read from the ammeter may not deviate
by more than ± 2.5% of the setting value. The tripping
values for the other current inputs should be checked
accordingly.

Function test
Disconnect all leads for adjusting the interposing C.T.s and
perform the following function test:
Load the generator with minimum 50% load. Assure that the
tripping of the generator C.B. does not cause un-wanted
damages (blackout).
To operate the differential relay use a shorting link
between one of the phase measuring sockets
and GND, e.g. connect Line to GND. The relay should trip
immediately. If no trip occurs, make sure
that the load current exceeds the set value.

How to control motor gearbox speed and friquency? If length of cable and dia given, how to measure the voltage drop?

0 Answers  

---

sir what is the purpose of SF6 in HT breaker and what is the pressure should be maintain in the breaker?

2 Answers   Kirloskar,

---

What are the safeties in elevators?what is the use of governor in elevator?

3 Answers   JLL,

---

What is the basic difference between 90% stator earth fault and 100% stator earth fault, and its phenmenona?

4 Answers   Reliance,

---

On a 3 winding transformer YNynd11, how do you apply REF protection to the Delta tertiary winding that is supplying auxiliaries to a substation?

0 Answers   Kwekwe Polytechnic,

---

---

what is maxemo work permit procedure

0 Answers  

---

Why 66KV is step down to 11KV and then 433v, not directly 66KV to 433v ?

2 Answers  

---

Anyone who can recommend an equivalent to Envirotemp FR3 of Cooper?

0 Answers  

---

Can we use a window type neutral CT instead of a bar type neutral CT. We have an issue with a neutral bar type CT of 800/1 ratio with a Circuit breaker NS800L shneider type, and we want to change it with a window type. Pls advise. Thanks

1 Answers  

---

What is the difference between Delta & Wye windings?

0 Answers  

---

11kV capacitor bank of rating 2.4KVAR, is charged with protective relays of only over current & Earth fault &.......without Over Voltage, Under Voltage & Neutral Displacement Relay. Is it advisable??

0 Answers  

---

what is the responsibility of C license holder in industry?

0 Answers  

---