Electrical Safety
What safety gear should be worn when using a multimeter with high voltages?
Insulated gloves and safety goggles
Alternating Current (AC) is current that?
What is current that Alternates its direction of flow through the conductor
What is the law that tells us how amps, volts, and ohms will relate to each other?
A ladder diagram is?
A symbolic representation of circuit logic
On an air cooled air conditioning system how many fan motors are there typically and what are they called?
Two fans. Indoor (evaporator) blower motor, and the Outdoor (condenser) fan motor.
Before using a multimeter, you should?
Check for visible damage to leads and ensure probes are in good condition
What position must a switch (contactor, relay, safety switch, etc.) be in order for a circuit to be on?
Closed
The watts a system is pulling is equal to
The volts applied to it multiplied by the the amps flowing through it.
In a ladder diagram, L1 and L2 represent?
Line voltage rails, with L1 on left and L2 on right
The component in system that lowers voltage for a safer, easier to handle, control voltage.
Transformer
Direct Current (DC) is defined as?
A continuous flow of electrons in one direction
How can you determine what the output voltage of a transformer will be?
The secondary and primary voltage are directly proportional to the number of loops in the secondary coil compared to the loops in the primary coil.
A high-pressure switch is used to?
Shut down the system when pressure exceeds safe levels
A relay functions as?
An electrically operated switch using low-voltage signal to energize high-voltage components
Which safety procedure is critically important when servicing HVAC equipment? (especially on large job-sites)
Lock-out/tag-out procedures
The voltage
What is the (theoretical) maximum power factor an electrical circuit can have?
1
Pictorial Diagram
A condensate float switch activates when?
Water begins to overflow
Why should you never assume power is off to equipment?
Electrical panels may be mislabeled or someone may have worked in the panel
What is a cycle in AC current?
The period of time required for voltage to peak in both directions and return to 0V
Start winding & Line of power that feeds the run winding.
In schematic diagrams, heavy lines typically represent?
Line voltage
What are the points that get "pitted" on a switch?
Contact points