Electrical Engineering Interview Questions

253

What is the role of the 50 STUB protection at a GIS 400KV substation with SIEMENS protection relays?

241

In a power conditoining unit (inverter) of a solar plant when we measure the d.c. current fed by different strings of solar plates to inverter, the current in the negative wire is less almost by 1 ampere to the current in its positive wire say current in positive wire 5 A , then current in negative wire of the same string is 4 A. Since the current entering should be equal to current leaving then why the current is noticably less in negative wire.

274

What is trip and closing coil in cb? Why need of them

216

what is the mechanical safety of DG ?

304

Please, if 1kw is equal to 1.25kva; how then do I know how many kva in 7.5kw?

215

We are planning to synchronized DG's with our captive plant in the event of black start of plant, but before sync we checked voltage of DG with our plant voltage and it varies from 5 V to 450 V. So in this condition how we can sync DG with plant ?

206

Two electric lamps 40 W, 220 V each are connected in series across 220 V. What is the power consumed by the connection?

223

what is the IPC ? & what the uses ?

Bhel,

201

Why 9KV surge arrester having 7.65KV of MCOV?

239

How do we calculate over and under frequency tolerance from generator data?

DPS,

196

CT Ratio of a energy meter connection is Red Phase : 100/5A, yello Phase : 50/5A & Blue phase : 100/5 A what is the overall Multiplication factor

232

I use 20 nos led tube 4feet, in pathway 100mtr approximate, so what size cable i use for lighting

241

Why the earth to phase voltage is high 250 compare to other two phases

217

What is the difference between security constraint unit commitment and security constraint optimal power flow?

286

Un-Answered Questions { Electrical Engineering }

What is Delta Connection? What is meant by Forward Delta & Reverse Delta & How Will be the Connection in Power Transformers?

984

In EDO ACBs what is a purpose of closing coil and motor, what is the operation of these devices are they inetconnected. means if we give supply to motor and by BCS we charge Closing coil,what exact is operation is and how it charge a spring of ACB. Sir if anybody has an wiring diagram please send me the link to operate and EDO breaker.

797

hi, in the event earth grounding is not available in a project, is there any other way to make the elcb work? fyi, i have an instant water heater (6.5kw) installed, however if there is grounding in the heating element inside the heater assembly, i will get grounded. thank you in advance to those who will answer my question.

753

why h parameter are called as hybrid parameter?

725

What is the formula to calculate distribution transformer De-rating on iron losses basis

637

i need mat lab program to find out the transmission line losses,regulation and losses

673

How to megger test 11 kV cable and the acceptance IR value

1647

Is it possible to make a 5P10/ CT Ratio 50/1A Burden 5VA

432

what is upper impedance and lower impedance of a distance relay

878

i want to run 11kv star connected motor in 6.6kv with delta connected throught inverter, is it possible?

825

Earth is a conductor or load?then ammeter connect to 3- phase supply,it shows the measurents or not?

930

what is level 2 automation?

1860

What is PQA???Applications........

1123

What is the earth treantment procedure?

735

What is tan delta & PPM in transformer? and whats its IS value?

792