Electrical & Instrumentation QA / QC

Instrumentation QC Inspector Course & Interview Questions

1. What are the parts of coaxial cables?
 Center Core
 Dielectric Insulator
 Metallic Shield
 Plastic Jacket
2. What is Junction Box?
 An earthed enclosure within which wires or cables can be safely connected
3. What are the Kinds of Metering Instrument?
 Conventional electronic and pneumatic transmitter
 Transducers
 Indicators
 Pressure Gage
 Thermocouples
 Resistance Temperature detectors
 Level Transmitter
 Instruments air line pressure gage
 Turbine positive displacement and magnetic flow meters
 Pilot Tube annular flow meters
 Temperature gage
4. What are the task in performing instrument loop checking?
 Conducted as per cable package and markings, Tagging and Wire color coding. Testing to be conducted or using test equipment or hand tools continuity test and referenced loop package documents
 Considering to identify the Instruments loop (either Closed Loop or Open Loop)
 Obtain Documents pertaining to the process loop in order to understand All devices and their intended functions

 Inspect the loop components through visual observation in order to ensure that the components are correctly installed
 The prepared approved Instrument loop package or folder shall be always implemented
5. What is instrumentation?
 Is a branch of science which deals with measurement and control of process variables such as pressure, flow, temperature, level and etc.
6. What are the kinds of pressure measurement?
 Pressure Gauges
 Draft Gauges
 Pressure Switches
 Pressure Transmitters
 Deferential Pressure Instruments
7. What are the Kinds of Smoke Detector?
 Air Sampling type detector
 Automatic fire detector
 Automatic Fire Extinguishing or suppression system operation detector
 Combination detector
 Electrical conductivity heat detector
 Fire-Gas Detector
 Fixed temperature detector
 Flame detector
 Heat detector
 Line-type detector
 Other Fire detectors
 Pneumatic rate-ofrise tubing heat detector
 Projected beam-type detector
 Radiant sensing fire detector
 Rate compensation detector
 Rate offrise detector
 Smoke detector
 Spark/Ember Detector

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Electrical QC Inspector Course & Interview Questions Part-2

31. What are Load Bank capacities?
 Single Block – Entire capacity of load bank applied, on/off, in one step increment
 Multiple Steps – Load bank capacity is divided into discrete increments for application in steps; defined in terms of load step resolution, which is the smallest step increment of load control. Steps can be coarse (50%, 33%, 25%) or fine (5KW, 1KW)
 Single Voltage – Designed for a specific voltage, typical of exercise load banks to 15KV.
 Multiple Voltage – Capable of dual or quad voltages. Typical of test systems. (Typical voltages 60HZ: 120/240, 208-240, 416-480; 50HZ: 190-220, 380-420; DC: 12-60, 125, 250) to 15KV.
 Single Frequency – Designed for a specific frequency
 Multiple Frequency – Capable of multiple frequency or AC/DC operation (Typical frequencies: 50-60-400HZ, DC)
32. What are some Load Bank Cooling systems?
 Natural Convection Air – 20 KW Maximum
 Integral Fan – Cooling fan included in load bank; up to 3000 KW.
 Radiator Airflow – Load bank installed in radiator fan airflow; up to 1000 KW
 Water – Cooling via heat transfer to water flow; water does not conduct electrical current. Open flow using commercial/natural water or closed loop using heat exchanger up to 1200 KW.
33. What are load bank enclosures?
 Portable – For factory, shop, field use, self-contained
 Stationary – For permanent installation at a specific site
 Duct Mounting – For permanent installation in radiator airflow
 Indoor – NEMA 1 enclosures
 Outdoor – NEMA 3R enclosures
34. What are load bank controls?
 Local – Control panel self-contained in load bank
 Remote – Control panel for remote operation
 Automatic – Wide variety of auto control available including auto on-off, auto load regulation, KW or reverse power response, computer control
35. What are load bank connections?
 Cable Set – Connection cable included with load bank. Typical of portable units
 Terminal Block – Power terminals for connection of building cables. Typical of stationary and duct mounted units.
 Plugs – To match commercial wiring devices, aircraft plugs, MIL-SPEC plugs, cam-lock connections.
36. What are load bank features?
 Short Circuit Protection – Load element branch circuit fuse or circuit breaker protection
 System Protection – Protected against running failures (fan fail, overtemp, overvolt, etc.)
 Control – Self-contained load control devices (contactors, relays, circuit breakers)
 Handling – Forklift channels, lifting eyes, casters on portable units.
 Instrumentation – Full instrumentation available: analog or digital; data acquisition systems
 Options – Many options available
37. What are the purposes of AC High Potential Test Set?
 This test set generates AC test voltages from 0-120,000 volts at currents between 0-5MA.

 The test set is used to evaluate insulating materials, resistive and reactive properties.
 The results are recorded as leakage current which is converted to resistance.
 The resulting resistance can be used together with the DC hi-pot test readings to determine the AC resistance component for insulation evaluation.
38. The purposes of Digital Low Resistance Ohmmeter (Kelvin Bridge)?
 The DLRO is a direct reading 100 Amp, 4 wire digital ohmmeter.
 The DLRO is used to measure the DC resistance of contacts in a conducting path.
 The DLRO is operated by applying a DC current through the desired conducting path.
 The readings (DC micro-ohms) indicate the resistance at the contacts. This data is used to determine the amount of heating that can occur at the contacts as a result of the current flow through this connection.
39. The purposes of DC High Potential Test?
 The test set generates DC voltages from 0-80,000 volts at currents between 0-10MA.
 The testing potential is applied across the insulating medium in question, (bushing, standoff, barrier, buss bar, open air gaps, etc) raised to published voltage stress standards and maintained for one (1) minute and lasting for 15 Minutes.
 The results are recorded as leakage current which is converted to resistance (typically megohms).
 The resulting resistance readings are used in determining the insulation integrity in medium voltage air circuit breakers.
40. The High Potential Electrical Operation Test?
 During this test the technician insures that all electrical functions of a circuit beaker or switchgear section(s) are operating properly and adhere to all customer and manufacturer’s specifications.
41. The Electrical Operation Such tests included?
 Close and trip coil operate within published ranges
 Mechanical Operation Test
 Multi-Voltage Test Set
 Overload Coordination Test Set
 Three Phase Primary Injection Test
 Optional Tests
42. Activities involves in close and trip coil operate within published ranges
 Control relay sequence and timing
 Auxiliary contact conductance
 Proper charging motor operation
 Meggar test insulation/components

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Electrical QC Inspector Course & Interview Questions Part-1

1. Types of Cable?
 XLPE PVC – Cross Link Polyethylene Polyvinyl Chloride
 Armored Cable
 Fiber Optic
 THHN/THWN – Thermoplastic High Heat Resistance Nylon coated Cable
 AWG – American Wire Gauge
 Ribbon Cable
 Coaxial Cable
 Mineral-insulated copper-clad cable
 Twinax Cable
 Flexible Cable
 Non-Metallic Sheathed Cable
 Metallic Sheathed Cable (or Armored Cable)
 Multicore Cable
 Shielded Cable
 Single Cable
 Twisted pair
 Twisting Cable
 FEP/SS. JKT. Cables
2. Kinds of Transformer Windings?
 Primary Windings
 Secondary Windings
3. Saudi Aramco Low Voltage wire color coding for AC Supply?
 P – Black
 N – White
 G – Green or Green with white with yellow tracer
4. Saudi Aramco Low Voltage wire color coding for DC Supply?
 P – Red
 N – Black
5. Saudi Aramco Low Voltage wire color coding for Three Phase system?
 L1 – Red
 L2 – Yellow
 L3 – Blue
 N – Black
 G – Green or Green with white with yellow tracer
6. Four Kinds of Saudi Aramco Project Phase and Activity code?
 Document Review
 Receiving Inspection
 Installation
 Pre-Commissioning
7. What are some contents of Surveillance Report
 Report Control No.
 Project Details
 Work Description

 Observation
 Comments or Recommendation
 Person’s Signatory
 Preventive Action
 Closed-Out Signatory
8. What are the some contents of Non Conformity Report (NCR)?
 Report Control No
 Project Details
 NCR Subject
 NCR Description and reference of violation
 Persons Signatory
 Corrective Action
 Executioner Personnel Signature
 Final resolution personnel signature
9. What are the Specific contents of project Method of Statement (MS) or Project Procedure?
 Scope
 Reference Documents
 Definitions and Abbreviations
 Reference Standard
 Health, Safety and Environment Policy
 Authorities and Responsibilities
 Methods and general guidelines
 Tools, Equipment and Materials
 Inspection
 Attachment
10. Inspection Level as per SAUDI ARAMCO
 Level 0 = Inspection Level 0 includes documentation requirements only, no vendor inspection required.
 Level 1 = Visual Inspection witnessing by inspector
 Level 2 = Certificates/Records to be checked by inspector
 Level 3 = Certificates/Data to be provided by vendor/Supplier/Manufacturer
11. Kinds of Switchgear?
 SF6 – Sulphur hexafluoride switchgear
 GIS – Gas Insulated Switchgear
 Mettal clad Switchgear
 LV Metal enclosed switchgear
12. What are the Task to be considered of conducting Medium Voltage circuit breaker testing?
 Visual and mechanical inspection
 Electrical Test
 Test Values
 Resistance Test
 Breaker triple and velocity test
 Pick-up voltage test on tripped and closed coil
 Tripped circuit breaker by operating protective relays

 Insulation resistance test
 Hi-potential Test
13. What are the required testing to be conducted for Power Transformer?
 Transformer Turns and Ratio Test (TTR)
 Winding Resistance Test (WRT)
 Megger Test/Insulation Resistance and Polarization index test
 Short Circuit test of full load test
 Open Circuit Test
 Hi-Potential test
 400 Hz. Induced Over voltage test
 Transformer oil test process
 Di-Electric strength test
 Water content (PPM) Test
 Inter facial Tension
 Acid Neutralization Number Test
 Rapid Pressure Relay
 Winding Temperature
 Transformer Calibration

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