MGVCL Exam Paper (30-07-2021 Shift 2)
Consider the following statements associated with Buchholz's relays.
Statement 1: Buchholz's relay is a current operated device.
Statement 2 : Buchholz's relay is placed between the transformer tank and the conservator.

Both Statement 1 and Statement 2 are FALSE
Statement 1 is TRUE and Statement 2 is FALSE
Both Statement 1 and Statement 2 are TRUE
Statement 1 is FALSE and Statement 2 is TRUE

ANSWER EXPLANATION DOWNLOAD EXAMIANS APP

MGVCL Exam Paper (30-07-2021 Shift 2)
Which one of the following statement is TRUE?

Underground cables are laid at sufficient depth to avoid being unearthed easily due to removal of soil.
In the cables, sheaths are used to provide enough strength.
The current carrying capacity of cables in DC is less than that in AC.
In the cables, the location of fault is usually found out by comparing the capacitances of insulated conductors.

ANSWER EXPLANATION DOWNLOAD EXAMIANS APP

MGVCL Exam Paper (30-07-2021 Shift 2)
The expression for voltage regulation of a short transmission line for leading power factor is given by: ____, where, 'I' is the line current, 'V_r' is the receiving end voltage, 'R' is the line resitance and 'X' is the line reactance.

(IXcosφ_r - IRsinφ_r)/V_r
(IRcosφ_r - IXsinφ_r)/V_r
(IRcosφ_r + IXsinφ_r)/V_r
(IXcosφ_r + IRsinφ_r)/V_r

ANSWER EXPLANATION DOWNLOAD EXAMIANS APP

MGVCL Exam Paper (30-07-2021 Shift 2)
The line currents in amperes in phases a, b and c respectively are 500 +j150, 100 – j600 and – 300 + j600 referred to the same reference vector with phase sequence of abc. Find the symmetrical component of currents.

Ia₀ = (100+j50) AIa₁ = (546.41+ j165.47) AIa₂ = (546.41-j165.47) A
Ia₀ = (100+j50) AIa₁ = (200+ j107.75) AIa₂ = (200-j107.75) A
Ia₀ = (100+j50) AIa₁ = (546.41+j165.47) AIa₂ = (-146.41-j65.47) A
Ia₀ = (100+j50) AIa₁ = (146.41+ j65.47) AIa₂ = (546.41-j165.47) A

ANSWER EXPLANATION DOWNLOAD EXAMIANS APP

MGVCL Exam Paper (30-07-2021 Shift 2)
Interposing current-transformer (CT) is used in differential protection of a transformer to

increase the sensitivity of the relay
limit the main CT secondary current
match the standard ratio of CTs used on both sides of the transformer winding
minimize the effect of saturation of the main CTs

ANSWER EXPLANATION DOWNLOAD EXAMIANS APP