EASQ ELECTRICAL APPLIANCE SERVICEPERSON (QUALIFIED) MARKING SCHEDULE. SECTION 1 Marks Reference Marking notes Qu 1 A 10 MΩ (2 marks)

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1 EASQ ELECTRICAL APPLIANCE SERVICEPERSON (QUALIFIED) MARKING SCHEDULE Notes: 1. (1mark) means that the preceding statement/answer earns 1 mark. 2. This schedule sets out the expected answers to the examination questions. The marker can exercise their discretion and decide on the overall accuracy of any answer that is presented in the candidate s own words. 3. Symbols and terms - alternatives Power W or P Voltage V or E or U Phase Active SECTION 1 Marks Reference Marking notes 1 A 10 MΩ 2 B The cross sectional area of the flexible cord conductors. 3 A OV 4 B Class II 5 D Two elements in parallel across the supply. 6 A Water - gas expelled. 7 B No earthing facility. 8 C Reverse the connections of the run winding. EASQ marking schedule 23 June

2 SECTION 1 Marks Reference Marking notes 9 B 20A 10 B 0.81A EASQ marking schedule 23 June

3 SECTION 2 Marks Reference Marking notes 11 (a) A centrifugal switch or a relay opens. Any one of: Reverse the connections on the start winding. Reverse the connections on the run winding. (c) Any one of: The motor would sit there and hum. The motor would not start. 12 (a) Any one of: Reverse connections to the field windings. Reverse connections to the armature windings (or brushholder connections). Any two of: Vacuum cleaner. Sewing machine. Powered portable hand tools. 13 (a) A standard split-phase motor. (c) 1. Centrifugal switch. 2. Start winding. 3. Run winding. Any one of: Reverse the connections on the start winding. Reverse the connections on the run winding. EASQ marking schedule 23 June

4 SECTION 3 Marks Reference Marking notes 14 (a) Earth continuity (Protective earthing conductor) test. Insulation resistance test. Earth continuity (Protective earthing conductor) test: Resistance function Lowest range 1Ω Maximum AS/NZS 3760: AS/NZS 3760: Insulation resistance test: Insulation resistance test function 500V d.c range 10,000Ω Minimum EASQ marking schedule 23 June

5 SECTION 3 Marks Reference Marking notes 15 Any three of: Check for obvious damage or defects in the plug. Check for discolouration that may indicate exposure to heat, chemicals and moisture. Check that the flexible cord is effectively anchored to the appliance and plug. Check that the inner cores of the flexible supply cord are not exposed or twisted. Check that the external sheath is not cut, abraded, twisted, or damaged to such an extent that the insulation of the inner cores is visible. Check that unprotected conductors or banding insulation tape are not in evidence. The insulated pins of plugs should be inspected for damage to the insulation. The current rating of the plug is consistent with the current rating of the appliance. (1½ marks) AS/NZS 3760: (a) Insulation resistance test. AS/NZS 3760: Insulation resistance test: Insulation resistance test function 500V d.c range 1 MΩ Minimum 17 Any two of: Check that any operating controls are in good working order i.e. they are secure, aligned and appropriately identified. Check that covers, guards and the like are secured in the manner intended by the manufacturer or supplier. Check that ventilation inlets and exhausts are unobstructed. AS/NZS 3760: EASQ marking schedule 23 June

6 SECTION 4 Marks Reference Marking notes 18 Correct polarity. Correctly connected fuse. Ammeter correctly connected. Heater correctly connected. Switch is on supply side of element. Working circuit. EASQ marking schedule 23 June

7 SECTION 4 Marks Reference Marking notes 19 I = P V = = 6.52A 20 R = V 2 P = 230 x = 26.45Ω 21 P = V 2 R = 240 x = W EASQ marking schedule 23 June

8 SECTION 5 Marks Reference Marking notes 22 Current rating. Voltage rating. Category of duty (Rupturing Capacity). Utilisation category (fusing factor) (Class). 23 Any two of: It will safely interrupt short circuit currents of much higher values. It is obtainable in a range of Utilisation categories (fusing factors). Reliable operation within prescribed limits. Better discrimination. Constant fusing characteristics. Faster operation/acting. 24 Any two of: The fuse carrier may be damaged if when the fuse wire blows under fault conditions. The fuse wire cannot safely interrupt short circuit currents of much higher values. Suitable fixing for the fuse wire is not generally available. The fuse wire is slower in operating under fault conditions. Circuit discrimination is compromised. 25 (a) A circuit breaker. It is the ratio of the MCB minimum tripping current to the MCB current rating. (c) The maximum current that a fuse-is designed to carry continuously. EASQ marking schedule 23 June

9 SECTION 6 Marks Reference Marking notes 26 (a) Either one: Power ceases to be supplied to the appliance. Just turning the switch to the OFF position. The appliance has been deliberately disconnected from the supply OR Appliance is switched off. Steps have been taken to prevent reconnection. 27 Any two of: Lock open the isolator. Disconnect the appliance. Disconnect the circuit supplying the appliance. 28 (a) Any two of: Lock the isolator in the off position. Lock the MCBs in the off position. Disconnect the flexible cable from the permanent connection unit. To ensure the personal safety of the person working on the equipment, by ensuring that the supply cannot be inadvertently switch back on. 29 To ensure that the test meter/instrument is operating correctly. To ensure that the equipment has been isolated before it is worked on. EASQ marking schedule 23 June

10 SECTION 7 Marks Reference Marking notes 30 (a) Any one of: Appliance 1 Or: Brown Phase Light blue Neutral Red Phase Black Neutral Any one of (but different from 30a): Appliance 2 Or: Red Phase Black Neutral Brown Phase Light blue Neutral Allow a (matching) earth but only if the answer is qualified with PEC is not connected to the appliance. 31 Any two of: Uncoiling the lead (if coiled). Using a lead with a larger current rating. Using an appliance with a lower current rating. 32 The current rating of the cord. 33 (3 marks) Alternative solutions include: A - N- E For active: - phase - live - line EASQ marking schedule 23 June

11 SECTION 8 Marks Reference Marking notes 34 A danger tag is used where turning on the point of isolation would cause personal harm or injury. Answer must include personal safety or avoidance of personal harm. 35 Ensure the correct isolating switch is selected. Ensure the isolating switch is in the OFF position. Each person must fasten a tag to the isolation switch. The tags are securely fastened to the isolating switch. (4 marks) 36 To prevent faulty or damaged electrical equipment from being further damaged or causing injury. 37 Test between phase and earth. Test between phase and neutral. EASQ marking schedule 23 June

12 SECTION 9 Marks Reference Marking notes 38 (a) To ensure the protection operates as fast as possible, to disconnect the faulty appliance and minimize shock. Any one of: To ensure that the phase, neutral and earth conductors are terminated at the correct terminals. To ensure that the phase is being switched in an appliance, and that the neutral and earth conductors are correctly connected. (c) To ensure that the insulation can withstand the voltage pressure. 39 (a) Any two of: OR A flashover or tracking could occur. Due to moisture inside the appliance. It could compromise the integrity of the insulation resistance. which could lead to current leakage dangerous touch voltages and tracking or flashover. Any two of: Under fault conditions, moisture decreases the resistance to earth. Increases the risk of shock hazard. OR Without a safe guard - (eg isolated supply or an RCD - this phrase is optional). The fault current can pass through the person, giving an electric shock. 40 The output voltage of the ohmmeter is insufficient to stress the insulation. EASQ marking schedule 23 June

13 SECTION 9 Marks Reference Marking notes 41 The overload current heats a bi-metal strip. The bi-metal strip bends when heated and trips the MCB. EASQ marking schedule 23 June