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Energy Management for Motor Driven Systems


Quiz Questions

1. A successful energy management process is marked by: maximizing production efficiency, minimizing energy consumption and maintaining a high energy load factor.
True
False
2. Energy management consists of a well structured team effort to create energy awareness: collect and organize energy cost and consumption data; identify, analyze and implement energy conservation opportunities; and monitor results.
True
False
3. Typical Energy Management Team Organization Chart is represented in ________________________.
Figure 1-1
Figure 1-2
4. In the rolling average method of energy accounting, you calculate billing data each month by dropping the oldest month from the total and adding the newest. This method eliminates widely fluctuating values due to variable meter reading dates or seasonal processes.
True
False
5. Sawmill Energy Consumption Disaggregation is represented in ________________________.
Figure 2-1
Figure 2-2
6. A voltage unbalance occurs when there are unequal voltages on the lines to a poly-phase induction motor. This unbalance in phase voltages causes the line currents to be out of balance. The unbalanced currents cause torque pulsations, vibrations, increased mechanical stress on the motor, and overheating of one and possibly two of the phase windings. Voltage unbalance has a detrimental effect on motors.
True
False
7. High temperatures are a strong indication of both energy wastage and pending failure.
True
False
8. System voltage can be modified by adjusting the transformer tap settings or installing automatic tap changing equipment where system loads vary greatly through the course of the day.
True
False
9. In a three-phase power system it is necessary to measure the following at each motor – phase to phase voltage between all three phases, current values for all three phases, power factor in all three phases, and operating speed of motor and driven load.
True
False
10. A diagram of a typical three phase power system serving a delta motor load configuration is shown in____________________________.
Figure 4-1
Figure 4-2
11. Part-load is a term used to describe the actual load served by the motor as compared to the rated full-load capability of the motor.
True
False
12. The synchronous speed of an induction motor depends on the frequency of the power supply and on the number of poles for which the motor is wound. The _______________________the frequency, the faster a motor runs.
Lower
Higher
13. MotorMaster+ software supports industrial energy management activities by providing:

  • A plant motor inventory module where motor nameplate data, operating information and field measurements are linked to utility, facility, and process information;
  • Capability to automatically estimate in-place motor load and efficiency;
True
False
14. Existing Motor Replacement Analysis is represented in ___________________________.
Table 7-1
Table 7-2
15. An AC motor turns at a speed determined by the AC frequency and its design (i.e. number of magnetic poles). This speed is absolutely exact in synchronous motors and only varies (with torque loading) by a few percent in induction motors.
True
False
16. A low power factor (approaching unity) indicates efficient use of the electrical distribution system while a high power factor indicates poor use of the system.
True
False
17. Real power is measured in _________________and apparent power is measured in ___________________.
Kilowatts (kW), kilovolt-amperes (kVA)
Kilovolt-amperes (kVA), kilowatts (kW)
18. Apparent power requirements before and after adding power factor correction Capacitors are represented in ________________ .
Figure 8-3
Figure 8-4
19. Short circuit MVA represents system impedance. It is the current (in millions of amperes) that would be drawn by a short circuit, multiplied by the no-load voltage of the system at the point of interest.
True
False
20. An excellent tracking tool for managing your motor inventory and keeping track of power supply and loading conditions is the ___________________software.
MotorMaster+
MATLAB7