Stationary Engineer Electric Graded A

Stationary Engineer Electric Graded A An AC circuit consists only of a pure inductance and a power source. The relationship between the voltage and the current in this circuit is that the ️current lags the voltage The power factor of a load is equal to the ____________ power divided by the ____________ power. ️True ; apparent A 10-ohms and 20-ohms resistor are connected in parallel. The total line current drawn by this parallel combination is 30 amps. Under these conditions, the line voltage will be ____________ volts. ️200 A 20-ohm resistor is connected in series with a parallel combination of two resistors, one of which is 10 ohms, the other 40-ohms. If the voltage across the parallel combination is 40 volts, the voltage across the 20-ohm series resistor is ________ volts. ️100 A certain 120-volts single-phase AC circuit has a power factor of 80 percent and a watt-meter reading of 1150 watts. The current drawn by the circuit is _________ amperes. ️12 If the voltage between lines of a 3-phase, 3-wire delta connected system is 2400 volts, then the phase voltage is _____________ volts ️2400 A circuit consists of an inductive reactance of 15 ohms and a resistor of 20 ohms in series across a 100 volts, 60 cycles AC supply. The current in this circuit is ____________ amperes. ️4 A 3 phase, 3 wire, 208 volt, 60 cycles AC service supplies a balanced load consisting of three 30 ohms resistors connected wye. The line current under these conditions os MOST NEARLY ___________ amperes. ️6.9 If the level of the electrolyte in a lead acid storage battery falls below the top of the plates because of evaporations under normal operating conditions, it is BEST to add ️Water A 600 volt cartridge fuse must have knife blade contacts if its current rating exceeds _____________ amperes. ️60 When the magnitude of the short circuit currents in a feeder circuit must be limited, this is USUALLY accomplished by means of ️reactors The cross sectional area in circular mils of a standard cable having 37 strands, each of which ha a diameter of 90 nils, is MOST NEARLY ️300,000 A coil having an average diameter of 4 inches is to be made up from a 1,260 ft long length of wire. The numbers of turns in this coil will be MOST NEARLY ️1,200 The device commonly known as a growler is FREQUENTLY used to ️test DC armature windings for shorts When a megger is applied alternately to the two leads of a direct current electrolytic capacitor, the reading will ️start at zero but increase gradually for one of the connections The device used to convert direct current to alternating current is called ️inverters Of the following conditions, the one which is MOST likely to cause flashing or excessive arcing from brush to brush in a motor is ️Excessively high voltage on the line The currents in the armature equalizer connections in a DC generator are ️alternating currents A generating station has one 1000 Kw and two 2000 Kw generators. To supply 2000 Kw MOST economically, the operating conditions should be ️one 2000 Kw generator at full load The terminal voltage of a DC shunt generator having an armature current of 100 amperes, an armature resistance of 0.02 ohms, and a generated E.M.F of 222 volts is MOST NEARLY ______________ volts. ️220 The number of poles in the field of an alternator generating voltage at a frequency of 60 cycles per