IEC FINAL EXAM YEAR 1 WITH 100% CORRECT ANSWERS.

What is the result if the neutral wire becomes open on a multiwire circuit having unequal loads? a. The load of higher resistance would overheat and probably be damaged. b. The load of lesser resistance would overheat and probably be damaged. c. No effect until one load is turned off or opens. d. No effect. a. The load of higher resistance would overheat and probably be damaged. Circuits 7 and 9 share a neutral. This is a multiwire branch circuit. If Ckt. 7 is drawing 13 amps and Ckt. 9 is drawing 16 amps, how much current is flowing in the neutral? a.3 b.13 c.29 d.16 3 Amps Brainpower Read More Previous Play Next Rewind 10 seconds Move forward 10 seconds Unmute 0:00 / 0:15 Full screen The Code reference that specifies the type of disconnecting means (circuit breaker for example) that can be used on a multiwire branch circuit that feeds devices mounted on the same yoke [a stack switch or a duplex receptacle for example] is ___.Note: Select N/A (not applicable) if there is not an NEC® requirement. a.Article 100 b.240.15(B)(1) c.404.8(A) d.N/A b. 240.15(B)(1) Voltmeters are connected in ___ with the load when used to measure voltage across a load in a circuit. Parallel The neutral has been removed from the neutral bar in the circuit shown in Figure 128.407. Lamp 3 is connected in ___ with Lamps 1 and 2. Series (3 wire parallel circuits turn to series when the neutral is disconnected from the neutral bar) What is the minimum number of receptacles required in an unfinished basement? a.2 b.4 c.1 d.0 c. 1 The overall diameter (including insulation) of a 250 kcmil THHN/THWN copper conductor is ___ inches? a..082 b..397 c..765 d..711 e..575 d. 711 NEC Chapter 9 Table 5 pg 701 What part of the NEC® is a reference for calculating conduit fill where all conductors are the same size? a.Article 100 b.Table 310.15(B)(16) c.Annex C d.Table 314.16(A) c. Annex C What is the minimum trade size Schedule 80 PVC required to contain four 8 AWG THHN/THWN copper conductors? a.1 b.3/4 c.11/4 d.11/2 of these b. 3/4 NEC Annex C Eleven #12, five #10, and six #6 THHN/THWN conductors will be installed in a run of EMT. The smallest trade size EMT you can use is ___. a.11/2 b.21/2 c.11/4 d.2 e.1 c. 11/4 NEC Chapter 9 Tables 4 and 5 A short length of EMT is run between two panels. The ampacity values for the conductors in this EMT need not be derated, as long as the length of the EMT does not exceed ___. a.12 inches b.18 inches c.24 inches c. 24 inches An extension ladder should extend ___ feet above the top of the building and be secured. b. three ___ can be described as the point of demarcation between where the serving utility ends and the premises wiring begins. a.Service point b.Attachment c.Mast service d.Lateral a. Service point Which term best describes a service lateral? ground feed ead drop ce ground ce entrance a. Underground feed How many kW does a 100-ampere residential service draw when fully loaded? a.10 kW b.240 kW c.100 kW d.24 kW d. 24kW 100A x 240V = 24,000 W OR 24kW If a 95-watt lamp operates for 11 hours, the utility will bill for ___ kWh. a.8.636 b.10.450 c.11.579 d.1.045 e.1.158 d. 1.045 95W x 11hrs = 1045-watt-hours 1045/1000 = 1.045 kWh What is the monthly energy cost to operate a 200-watt high-pressure sodium lamp? Electricity costs $0.11 per kW-hr and the lamp will be ON for 12 hours per day. There are 30 days in a billing month. a.$7.92 b.$8.80 c.$15.94 d.$6.60 e.$660 a. $7.92 200W x 12hrs x 30 days = 72,000 72,000/1000 = 72kWh 0.11 x 72kWh = $7.9