Answer Posted / ram niveth

REF is a backup protection for transformer incipient
faults.
if differential fails REF comes on line.
if both protections are used , usually REF time setting
will be less than differential setting

what is the clear formula to calculate cable size for a load

1958

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pls tel me the electric train traction motors name plate details like rpm,torue,voltage,amps,watts..ect..

2047

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I want single line diagram for AMF & DG syncronizing panel

7179

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HELLO EVERYONE, I RECENTLY HAVE FOUND ONE PROBLEM, I WAS TAKING NO LOAD TRIAL OF AN HT MOTOR 920 MOTOR , 1440 RPM , 6.6 KV, WITH AUTO TRANSFORMER. AT 450 V, LOAD WAS 40 AMP AND SPEED WAS 250 RPM. BUT AS WE INCREASE VOLTAGE FROM 450 TO 480V, LOAD BECOME 41 AND SPEED REDUCED TO SOME RPM . SO WHICH PHENOMENON ACTED HERE FOR REDUCING SPEED.?? AND IS IT HAPPENING ALWAYS OR IT IS RARE? I ALSO HAVE FACED SUCH PROBLEM WITH FEW LT MOTOR ALSO.

1942

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Define what is the function of anti-pumping in circuit breaker?

1302

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I am getting above 60 V as open delta voltage against single phase unit ICT at tertiary delta formed and ICT getting trippped on NDR. ICT tested and found in order. PTs provided on tertiary are tested and in order. what may be the reason?

1851

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can the measured percentage error during calibration of single phase energy meter be negative?

2389

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How to check the Bushings of the transformer?

1803

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What is Anemometer used to measure?

1109

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1508

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what is the difference between directional & non directional earth fault with example please explain.

1840

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Air circuit breaker safety

1401

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2187

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How to define Kirchhoff current law and voltage law along with simply examples.

1758

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Plz tell me how we can find that particular company has vacancy or not

2260

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