Reference no: EM133091622

Electrical Systems Design

Task A - Design project

Question 1: As part of the electrical contract, the client is considering an electric vehicle charging unit in the car park supplied from the existing TN-C-S supply in the main hotel building. The IET Code of Practice for Electric Vehicle Charging Equipment Installations recommends a TT earthing arrangement for the unit.

Draw a fully labelled circuit diagram illustrating the three-phase 40o V supply system and earthing arrangement from the sub-station transformer through to the charging unit. The diagram should show the total earth fault loop path for the charging unit.

Your diagram does not need to show the complete detail of distribution boards, metering or consumer control equipment although the diagram should, as a minimum, indicate a connection point for each item of equipment.

Question 2: a) Select, using manufacturers' data, suitable luminaires for all parts of the pool/cafe block with
exception of the sauna. Your selection should be based on
• energy efficiency
• environment/external influences
• aesthetics
• Your selection does not need to take into consideration suitable levels of illumination for the purpose of this project or any outdoor lighting.

b) Show, on either electronic or hard copies of the drawing, positions of socket-outlets and fused connection units for the new hotel block giving consideration to the following items of equipment in each room:
• kettle
• TV
• provision for phone charging and/or laptop use
• supply to a 70o W air handling unit for heating/cooling (installed by specialist)
• electric towel rail.

c) Show, on either electronic or hard copies of the drawing, positions of the luminaires selected giving each type a suitable form of identification on a separate key.

d) Show, on either electronic or hard copies of the drawing, how each circuit in the new hotel extension is to be arranged. The arrangement must take into account that a fault in any one room must not affect another room.

e) Show, on either electronic or hard copies of the drawing, any further distribution boards that may be required in the hotel extension.

f) Show, on either electronic or hard copies of the drawing, how each lighting circuit in the new pool/cafe block is to be arranged including switching.

g) Give each circuit a unique form of identification.

h) Complete the legend on the drawings using recognised symbols and descriptions for each symbol used on the drawings.

Question 3: Select, with the aid of manufacturers' data, a suitable range of circuit protective devices for this
contract. Your selection should be based on the following:
• Prospective short circuit currents
• Requirements for additional protection and special locations.

Question 4: This question may be answered using the Table 1 or Table 2. It is strongly recommended that you use
pencil when completing the table to allow for recalculation of figures.
Determine, for every final circuit in the cafe/pool block, each of the following.
a) Design current (lb)
b) Nominal rating and type of protective device (In)
c) Method of installation reference
d) Rating factors that apply
e) Minimum cross-sectional area of live conductors for current capacity and voltage drop
f) Actual voltage drop.
g) Maximum permissible disconnection time for each circuit as given in BS 7671.
h) Earth fault loop impedance
i) Maximum earth fault loop impedance as stated in BS 7671.

Question 5: Determine, for one of the circuits supplying the fridges, the minimum possible cross sectional area of cpc which will satisfy the requirements disconnection as ADS under earth fault conditions and the adiabatic equation as Regulation 543.1.3 in BS 7671.

Question 6: For this question, use the table below. More copies may be made as necessary.
a) Determine the maximum demand for the pool/cafe block electrical installation before the application of diversity.
b) Determine the maximum demand for the pool/cafe block electrical installation following the application of diversity.

Question 7: Explain, with the aid of a diagram, how electric shock protection is provided by one of the shaver points in the hotel extension bathrooms using the Protective Measure: Electrical Separation.

Question 8: List, using the box below, five typical extraneous conductive parts and five typical exposed conductive parts that may be found within this entire complex.

Question 9: Complete the box below relating to earthing and bonding. so Complete the box below relating to isolation and switching.

Attachment:- Electrical Systems Design.rar