Exams › GATE › Technical

The table lists two instrument transformers and their features: Instrument Transformers | Features X) Current Transformer (CT) Y) Potential Transformer (PT) P) Primary is connected in parallel to the grid Q) Open circuited secondary is not desirable R) Primary current is the line current S) Secondary burden affects the primary current The correct matching of the two columns is

1. X matches with P and Q; Y matches with R and S.
2. X matches with P and R; Y matches with Q and S.
3. X matches with Q and R; Y matches with P and S.
4. X matches with Q and S; Y matches with P and R.

Correct answer: X matches with Q and R; Y matches with P and S.

Solution

Current Transformers (CT) are designed to measure line current, hence their primary is connected in series (not parallel), and an open-circuited secondary is undesirable as it can lead to high voltage. Potential Transformers (PT), on the other hand, are connected in parallel to the grid, and the secondary burden does affect the primary current, making the correct matches Q and R for CT, and P and S for PT.

Related GATE Technical questions

• If the input x(t) and output y(t) of a system are related as y(t) = max(0, x(t)), then the system is
• Two discrete-time linear time-invariant systems have impulse responses h1[n] = δ[n−1] + δ[n+1] and h2[n] = δ[n−1] + δ[n+1], where δ[n] is the Kronecker delta. The overall system is
• Consider a power system consisting of N number of buses. Buses in this power system are categorized into slack bus, PV buses and PQ buses for load flow study. The number of PQ buses is N_L. The balanced Newton-Raphson method is used to carry out load flow study in polar form. H, S, M, and R are sub-matrices of the Jacobian matrix J as shown below: [ΔP] [ΔQ] = J [Δδ] [ΔV], where J = [H S M R] The dimension of the sub-matrix M is
• Inductance is measured by
• In the Nyquist plot of the open-loop transfer function G(s)H(s) = (3s + 5)/(s - 1) corresponding to the feedback loop shown in the figure, the infinite semi-circular arc of the Nyquist contour in s-plane is mapped into a point at
• Consider a unity-gain negative feedback system consisting of the plant G(s) (given below) and a proportional-integral controller. Let the proportional gain and integral gain be 3 and 1, respectively. For a unit step reference input, the final values of the controller output and the plant output, respectively, are G(s) = 1/(s - 1)

⚔️ Practice GATE Technical free + battle 1v1 →