Basic electrcity Flashcards
What percentage of service calls are electrical?
85%
Who sets the standard for electrical code?
National Electrical Code
What is voltage?
The force that pushes current through wire.(Potential Energy)
What is amperage?
Amount of current flowing through a wire. (Packages)
What are Ohms?
Resistance to electrical flow.
What is a Watt?
Power Consumed
What are conductors?
Material that offers very little resistance to the flow of electricity.
What are insulators?
Material that offers a lot of reinsurance to flow. Tightly bound electrons that create an outer valance.
What is a load?
Converts electrical energy to some other form of energy to do work.
Loads found on an oil burner?
Motors,electromagnetic coils,transformers,heaters.
Parts of a circuit?
Source,switch, load,conductor
What is a short circuit?
Running a conductor from the source without a load.
What is Ohms law?
It takes one bolt to push one amp through one ohm.
What is the Ohms law formela?
E
I R
What is the power formela?
P
I E
What is a series circuit?
There is only one path for electrical current through loads.
What is a parallel circuit?
Has separate branches for each load. That way if one circuit goes out it won’t affect the others.
What is D.C.?
Direct Current. Comes from battery’s. Only flows in one direction.
What is AC?
Alternating Current. Made by generators. Travels both ways.
What is BX?
Armored cable with no ground wire.
What is MC?
Armored Cable with green insulated ground wire.
What is greenfield?
Armored cable with no wires in it.
What is a switch for?
To stop the flow of electricity.
For a switch to safely control a load on a oilheat system it must be located in the ,never in the .
L1, Nuetral
What is SPST?
Single Pole Single Throw.
What is DPST?
Double Pole Single Throw. Can make or break two deprecate circuits agh the same time.
What is a relay?
When a switch is sense to be normally open or normally closed.
What is bimetal?
Two different strips of metal fused together. One end is secured the other under a electric heater. As it heats the two metals expand at different speeds.
What is a solenoid?
A coil which creates a magnetic field.
What measures voltage?
Voltmeter which measures the difference in electric pressure between two points.
What does an ammeter measure?
Amps
What should you know when measuring with you ammeter?
- Type of circuit
- Design ampacity
- Design current draw of the loads.
Where can you find the design current draw of a load?
Eating Plate.tells you the design current draw in Amps for steady normal state operation.
What is used to measure resistance?
Ohmmeter. Measures resistance between two points.
How do you use an ohmmeter?
Shut of power due to ohmmeter has is own battery. Apply’s a steady voltage from the meters battery to test resistance.
What is continuity?
A measurement of a complete circuit.
What are some common causes of overloads?
- To many devices on circuit
- devices working to hard
- damaged devices
- surge when motor starts
What are fuses?
One time safety devices. Protect against to much current.
What’s is electricity?
Movement of electrons from molecule to molecule of a conductive material.
What are the parts of a circuit?
Source,switches,conductors,load
How is wore sized?
(AWG) American Wire Gusge
What size is thermostat wire?
18 Gauge
Good for 5 Amps
Sizes of wire and amp rating?
16/extension chords/10A 14/Romex/ 15A 12/Appliances/20A 10/pumps/30A 8/dryers/40A
What are the styles of wire?
- solid
- stranded
- cable
- Romex
Different types of Romex?
- white 14 gauge
- yellow 12 gauge
- orange 10 gauge
Styles of copper tubing?
Soft Drawn
Hard drawn
Soft drawn tubing?
- Comes in 50/100FT Rolls
- Measured by outside diameter
Hard drawn tubing?
- Comes in 10/20FT
- measured by inside diameter
- ACR measured outside diameter.
Types of copper tubing?
M,L,K
M copper tubing?
- Red
- Thinnest
- Non potable water, mechanical systems
L copper tubing?
- Blue
- Medium Thickness
- Potable Water, AC/R
K copper tubing?
- Green
- Thickest wall
- Direct bury,potable water,Gas
What is soldering?
Process using heat and alloy to join copper together.
At what temperature does soldering occur?
850 Degrees
What is soft solder made of?
95 % Tin
5 % Antimonium
What does DVOM stand for?
Digital Volt Ohm Meter
V- - - -
______ ?
Volts DC ( Battery’s)
What is a capacitor?
Electrical storage device
Types of capacitors?
Start & Run
What is a start capacitor used for?
Start motors, stronger
What is a run capacitor used for?
Gives extra ump
What is a microfarad?
Electrical boost, how a capacitor is measured.
How do you know if a capacitor is good?
If microfarads go up then down and reverse on it’s own.
How do you know if a capacitor is bad?
If it reads zero Ohms or overload.