HVAC/R Q&A
list the different types of electrical diagram - (correct answer)Ladder,schematic,
Factual,field connection, Component lable
which diagram is the most useful for understanding - (correct answer)Ladder
Decribe the ladder diagram - (correct answer)The "L1" and "L2" designations refer to
the two poles of a 120 VAC supply unless otherwise noted. L1 is the "hot" conductor,
and L2 is the grounded ("neutral") conductor. These designations have nothing to do
with inductors, just to make things confusing. The actual transformer or generator
supplying power to this circuit is omitted for simplicity
what information does a point to point diagrams given the techcian - (correct answer)the
actual wire routing to and from each terminal connection
what is the difference between a load and a control - (correct answer)Loads use power.
Controls either let power pass or they do not let it pass
Why is there a potential of 24 volts between the R terminal and the other terminals on a
thermostat sub base when the thermostat is not calling - (correct answer)The common
side of 24 volts is supplied through the coils of the devices that are not operating
A voltage reading across a set of contacts indicates that - (correct answer)The contacts
are open
what other diagrams are similar to point-to-point diagrams - (correct answer)Pictorial
diagrams and label diagrams
why are relay coils and contacts not shown in the same place on a schematic diagram -
(correct answer)because components are placed by their function in the circuit, not their
actual physical location. The coil and contacts are not in the same circuits.
list the different types of electrical diagram - (correct answer)Ladder,schematic,
Factual,field connection, Component lable
which diagram is the most useful for understanding - (correct answer)Ladder
Decribe the ladder diagram - (correct answer)The "L1" and "L2" designations refer to
the two poles of a 120 VAC supply unless otherwise noted. L1 is the "hot" conductor,
and L2 is the grounded ("neutral") conductor. These designations have nothing to do
with inductors, just to make things confusing. The actual transformer or generator
supplying power to this circuit is omitted for simplicity
what information does a point to point diagrams given the techcian - (correct answer)the
actual wire routing to and from each terminal connection
what is the difference between a load and a control - (correct answer)Loads use power.
Controls either let power pass or they do not let it pass
Why is there a potential of 24 volts between the R terminal and the other terminals on a
thermostat sub base when the thermostat is not calling - (correct answer)The common
side of 24 volts is supplied through the coils of the devices that are not operating
A voltage reading across a set of contacts indicates that - (correct answer)The contacts
are open
what other diagrams are similar to point-to-point diagrams - (correct answer)Pictorial
diagrams and label diagrams
why are relay coils and contacts not shown in the same place on a schematic diagram -
(correct answer)because components are placed by their function in the circuit, not their
actual physical location. The coil and contacts are not in the same circuits.
