Question 1

Where will a computer-based Building Management System usually not be found?&#10;A)Car manufacturing plant&#10;B)Public hospital&#10;C)Prison&#10;D)500-person office building&#10;E)100-room hotel

Accepted Answer

A computer-based Building Management System is typically not found in a car manufacturing plant as it deals more with controlling and monitoring the HVAC systems and energy usage in buildings rather than manufacturing processes.

Question 2

What is an air thermostat?&#10;A)Air temperature-operated switch&#10;B)Air temperature sensor&#10;C)Controller&#10;D)Humidity monitor&#10;E)Air speed indicator

Accepted Answer

An air thermostat is an air temperature-operated switch that controls the heating or cooling system in a building. It senses the air temperature and activates the HVAC system to maintain a desired temperature.

Question 3

How often does the Building Management System communicate data with sensors and actuators?&#10;A)Once per hour&#10;B)Continuously&#10;C)Every few seconds&#10;D)Daily&#10;E)Annual reports

Accepted Answer

The Building Management System needs to constantly monitor and adjust the building's environment, so it needs to communicate with sensors and actuators frequently, every few seconds.

Question 4

What forms does Building Management System data not take when passing through the communications cabling?&#10;A)Light pulses through fibre optic cables&#10;B)Alternating current of over 1.0 amp&#10;C)Internet protocol data packets&#10;D)Electrical direct current below 0.10 amp&#10;E)Voltage of 10 volt maximum

Accepted Answer

Building Management Systems (BMS) typically do not use alternating current of over 1.0 amp for data transmission through communications cabling. Data is usually transmitted using low voltage signals, light pulses through fiber optic cables, internet protocol data packets, or electrical direct current, ensuring safety and efficiency in communication. High currents like 1.0 amp are not suitable for data transmission in such systems.

Question 5

What does a CHP plant do?&#10;A)Burns natural gas to generate hot water heating&#10;B)Generates electricity for the national grid&#10;C)Provides emergency power when public supply fails&#10;D)On-site gas turbine or reciprocating engine drives an alternator while engine cooling water heats the building&#10;E)Gas turbine engine drives an alternator in a public supply power station

Accepted Answer

A CHP (Combined Heat and Power) plant is designed to generate electricity and capture and use waste heat from the process. In this case, an on-site gas turbine or reciprocating engine drives an alternator to generate electricity while the engine cooling water is used to heat the building, making it a more efficient use of energy compared to just generating electricity alone.

Question 6

A 30 kW heat emitter has a flow water temperature of 82^oC while return water leaves at 71^oC. Specific heat capacity of water is 4.2 kJ/kg K. Pipe heat emission amounts to 10% of emitter output. Which of these is the water flow rate?

A)0.72 kg/s
B)1.4 l/s
C)1.4 kg/h
D)0.72 kg/h
E)Cannot be found from this information

Accepted Answer

We can use the following formula to calculate water flow rate:

$\dot{Q}=\dot{m} c_p \Delta T$

where:

$\dot{Q}$ = heat output of emitter = 30 kW
$\dot{m}$ = mass flow rate of water
$c_p$ = specific heat capacity of water = 4.2 kJ/kg K
$\Delta T$ = temperature difference = (82 - 71) = 11 °C

We also know that pipe heat emission is 10% of the emitter output, so the total heat output is:

$\dot{Q}_{total} = 1.1 \dot{Q}$

Substituting the values:

$\dot{Q}_{total} = 1.1 	imes 30 = 33 kW$

Now, we can use the formula to calculate mass flow rate:

$\dot{m} = \frac{\dot{Q}_{total}}{c_p \Delta T}$

Substituting the values:

$\dot{m} = \frac{33 	imes 10^3}{4.2 	imes 11} = 722.2 	ext{ kg/h}$

Converting to kg/s:

$\dot{m} = \frac{722.2}{3600} = 0.2 	ext{ kg/s}$

Therefore, the water flow rate is 0.72 kg/s, which is the closest option to our calculated value.

Question 7

Which of these is the equivalent length for a pumped heating water system circulation?&#10;A)Total length of all pipes plus 25%.&#10;B)Total length of the longest flow and return circuit&#10;C)Total length of all pipes in the heating system&#10;D)Length of the longest circuit to the furthest heat emitter&#10;E)Flow and return circulation which creates the pump pressure rise

Accepted Answer

The answer of Which of these is the equivalent length...

Question 8

Which units specify pump pressure rise? A)m H₂O B)psig C)kN/m² D)mb E)mm mercury Hg

Accepted Answer

The answer of Which units specify pump pressure rise? A)m H₂O B)psig C)kN/m² D)mb E)mm...

Question 9

Which of these chemical symbols is correct? A)N₂ nitrous oxide B)O2 oxygen C)O₂ ozone D)CO₂ calcium bicarbonate E)H₂O hydrogen oxide

Accepted Answer

O2 is the correct chemical symbol for oxygen. The other options either contain incorrect symbols, are not a single element, or do not exist in chemistry (e.g. hydrogen oxide).

Question 10

What does stoichiometric ratio mean?&#10;A)Poor combustion&#10;B)Optimum efficiency&#10;C)Maximum oxygen in flue gas&#10;D)Maximum carbon dioxide in flue gas&#10;E)100% excess air provided

Accepted Answer

The answer of What does stoichiometric ratio mean?&#10;A)Poor combustion&#10;B)Optimum efficiency&#10;C)Maximum...

Deck 7: Heating