Preview Questions Substation Technician | Role Specific Skill

Question 1: What is the first step when diagnosing a fault in a circuit breaker that fails to close?

Which action should you take?

Choose only one option

Measure the arc interruption capacity of the breaker

Check the closing coil and associated control circuits

Inspect the breaker's mechanical linkages

Test the breaker's insulation resistance

Question 2: What is the most important consideration when testing for partial discharge in a high-voltage cable?

Which action should you take?

Choose only one option

Testing the cable under a lower voltage than its rated capacity

Using a high-precision capacitance meter to detect small leaks

Checking for physical wear and tear in the cable

Testing under normal operating conditions

Question 3: Which test is most commonly used to detect potential partial discharge activity in a transformer?

Which action should you take?

Choose only one option

Partial discharge (PD) testing

DC insulation resistance test

Power frequency withstand test

High-voltage breakdown test

Question 4: What is the effect of a high ratio of transformer winding resistance to reactance?

Which action should you take?

Choose only one option

Increased likelihood of overheating

Improved efficiency during operation

Increased insulation breakdown

Reduced power loss in the transformer

Question 5: In the event of a busbar fault, which of the following is the most likely cause?

Which action should you take?

Choose only one option

Grounding system failure

Insufficient insulation resistance

Faulty busbar protection settings

Overload from connected equipment

Question 6: What is the purpose of a Buchholz relay, and how do you maintain it?

Which action should you take?

Choose only one option

The Buchholz relay measures transformer temperature and should be checked quarterly

The Buchholz relay is used for overcurrent protection and should be inspected annually

The Buchholz relay detects gas accumulation and oil movement in a transformer and should be tested regularly for accurate operation

The Buchholz relay detects faults only during heavy load conditions