Topics: All categories in the pool
1: The best way to determine the voltage requirement for an electrical component is to
- read the voltage with a mulitmeter
- determine the capacity of the service panel
- check with the utility company
- read the nameplate data
2: A compressor in which the increase in vapor pressure is attained without changing the internal volume of the compression chamber is called
- neutral chamber-type compressor
- negative displacement compressor
- non-positive displacement compressor
- non-volumetric displacement compressor
3: One atmosphere equals
- 29.4
- 14.7
- 0 psig
- 0 psia
4: Absolute pressure is
- Gauge Pressure
- Atmospheric Pressure
- Gauge + Atmospheric Pressure + Pi
- none of the above
5: one BTU equals
- 3.41 hp
- 31.4 hp
- 12,000 hp
- Pi
6: What is the voltage of each leg to ground of a three-phase motor with a 460v supply voltage?
- 120v
- 240v
- 208v
- 277v
7: Megaohm meter's main function is
- to detect weak motor winding insulation of a refrigeration or air conditioning compressor by creating high DC voltages to the compressor
- to detect very high resistances to ground of refrigeration or air conditioning compressors
- to test very high value capacitors for large 3-phase refrigeration compressors and blower motors.
- Both a and b are correct
8: Capacity control on a centrifugal compressor is accomplished by the
- post-rotational guide vanes
- check valves
- pre-rotational guide vanes
- slide vanes
9: The best way to detect ammonia in brine is
- potassium of line
- carbonation of soda
- CO2 gas
- nessler regaent
10: When using nitrogen for brazing, the pressure should be:
- Very low
- 125 psig
- 50-100 psig
- Slightly below atmospheric
11: Which occupancy can ammonia be used in?
- commercial
- depends on the quantity of freon
- redifential
- industrial
12: A chiller entering and leaving temperature difference is?
- 5 degrees F
- 10 degrees F
- 50 degrees F
- 20 degrees F
13: In a motor, an internal overload might open if
- there's a direct short
- there's an open start winding
- there was a high pressure refrigerant was used for a low pressure system.
- there's an excess current draw through the motor
14: The maximum permissible amperage draw for a 40VA transfomer with a secondary voltage of 24V is
- .1
- .8
- 1.2
- 1.7
15: A 50 VA control transformer with a 25 volt control output would be rated for _________ amps.
- There isn't enough information to answer.
- 1250
- 2.5
- 2
16: Two systems using separate refrigerants that are superimposed upon one another is called
- cascade
- booster
- indirect
- single stage
17: The dial of a pressure gauge, when installed on the high side of a system be graduated 1.2 times the designed pressure.
- True
- False
18: Indirect systems using Group II refrigerants
- shall be used for mechanical equipment only
- shall be used in refrigeration system less than 1,000 lbs
- shall have all refrigerant containing parts except piping, installed in a Class T machine room
- shall be used in refrigeration system in excess of 1,000 lbs
19: On an air cooled condenser, if the ambient air is 35F and dropping, what's its effect to the condensor?
- it would make the condenser less efficient
- it would cause the condenser to sweat
- it would have no effect on the condenser
- it would make the condenser more efficient
20: The solution that leaves the concentrator in an absorption chiller is referred to as the
- weak solution
- absorbed solution
- diluted solution
- strong solution
21: What is the state of the refrigerant leaving the evaporator?
- a high temperature superheated vapor
- low temperature superheated vapor
- a high temperature subcooled liquid
- a low temperature subcooled liquid
22: Volts x amps equals
- Watts
- Inductance
- Ohms Law
- Impedance
23: A run capacitor is wired in series with the _____ windings.
- start
- common
- run
- start capacitor
24: A Lithium-bromide system is an absorption system that
- uses ammonia as a refrigerant and lithium bromide as an absorbent
- uses water as a absorbent and lithium bromide as a refrigerant
- uses water as a refrigerant and lithium bromide as an absorbent
- uses salts as an absorbent and lithium bromide as a refrigerant
25: Three-phase motors have what type of windings?
- three run windings and 3 start windings
- three run windings
- one start winding and one run winding.
- three start windings