Elec Flashcards
What are the voltage ratings and colour codes for rubber gloves from class 00 to 2
- class 00: 500V Beige
- class 0: 1000V Red
- class 1: 7500V White
- class 2: 17000V Yellow
What are the 5 emergency procedures after an electrical shock?
- Remove the victim
- Prevent further injury
- Send for help
- Eliminate the danger
- Report the incident
What are ammeters?
Inserted in series in a circuit to measure current.
What range of voltages and currents refrigeration mechanics work with?
5 VDC - 600 VAC, 20 mA - several hundred Amps
How is ampere expressed as in relation to coulomb
I=Q/t
What’s the process of producing EMF by adding heat to 2 dissimilar metals
Seebeck Effect
What are thermocouples
Thermoelectric generators that change heat into EMF
What are the 6 sources of emf?
Magnetic
Chemical
Friction
Heat
Pressure
Light
What current can cause involuntary muscle loss?
> 15mA
What are the four factors that affect current on the human body
-Area of contact
-Pressure
-Skin resistance
-Point of contact
What are megohmmeters?
Used to test electrical insulation resistance by applying a high voltage (>10 kV) typically at 500 VDC with minimum IR of 1 MO
What is Kirchoff’s Current Law?
Total current or charge entering a junction is equal to the charge leaving the junction:
I (exiting) + I (entering)=0
What is Kirchhoff’s Voltage law
The sum of all voltage drops in a series circuit equals the total applied voltage
E = V¹ + V² + Vn
Phi Φ
Magnetic flux
Residual magnetism
Ability for a material to remain magnetic after the magnetic force has been removed