# Direct Current

on . Posted in Electrical Engineering

Direct current, abbreviated as DC, is an electrical current that flows in one direction through a conductor.  Unlike alternating current (AC), which periodically reverses direction, DC flows consistently in one direction.  DC is generated by a variety of sources, including batteries, solar cells, and generators.  It is commonly used in a variety of applications, such as electronic devices, motors, and electroplating.  DC is also used in some transmission and distribution systems for electricity, particularly in certain high-voltage applications.

The properties of DC make it well suited for certain applications.  For example, DC motors are often preferred over AC motors for applications that require precise control, such as robotics or manufacturing equipment.  DC is also commonly used in electronic devices, such as computers and televisions, as the internal components typically operate on DC power.  One disadvantage of DC is that it is generally less efficient to transmit over long distances than AC, due to the need for high voltage transmission lines and expensive transformers.  As a result, most long distance transmission and distribution of electricity is done using AC.

DC is an important form of electrical current that is used in a wide range of applications.  Its properties make it particularly well suited for certain types of devices and systems, and it is likely to remain an important technology for years to come.

### Basic Electric Formulas

$$V$$ = Voltage  -  $$I$$ = Amps  -  $$PF$$ = Power Factor  -  $$\eta$$ = Efficiency  -  $$HP$$ = Horsepower

To Find Direct Current Alternating Current
Single Phase Two Phase Four Wire Three Phase
Amperes when HP is known $$\large{\frac{ HP \; 746 }{ V \; \%\eta } }$$ $$\large{\frac{ HP \; 746 }{ V \; \%\eta \; PF } }$$ $$\large{\frac{ HP \; 746 }{ V \; \%\eta \; PF \; 2 } }$$ $$\large{\frac{ HP \; 746 }{ V \; \%\eta \; PF \; 1.73 } }$$
Ampere when kW is known $$\large{\frac{ kW \; 1000 }{ V } }$$ $$\large{\frac{ kW \; 1000 }{ V \; PF } }$$ $$\large{\frac{ kW \; 1000 }{ V \; PF \; 2 } }$$ $$\large{\frac{ kW \; 1000 }{ V \; PF \; 1.73 } }$$
Amperes when kVA is known  - $$\large{\frac{ kVA \;\; 1000 }{ V } }$$  $$\large{\frac{ kVA \;\; 1000 }{ 2 \; V } }$$ $$\large{\frac{ kVA \;\; 1000 }{ 1.73 \;V } }$$
Kilowatts $$\large{\frac{ V \; I }{ 1000 } }$$ $$\large{\frac{ V \; I \; PF }{ 1000 } }$$ $$\large{\frac{ V \; I \; PF \; 2 }{ 1000 } }$$ $$\large{\frac{ V \; I \; PF \; 1.732 }{ 1000 } }$$
Kilovolt Amperes kVA  - $$\large{\frac{ V \; I }{ 1000 } }$$ $$\large{\frac{ V \; I \; 2 }{ 1000 } }$$ $$\large{\frac{ V \; I \; 1.732 }{ 1000 } }$$
Horsepower $$\large{\frac{ V \; I \; \%\eta }{ 746 } }$$ $$\large{\frac{ V \; I \; \%\eta \; PF }{ 746 } }$$ $$\large{\frac{ V \; I \; \%\eta \; PF \; 2 }{ 746 } }$$ $$\large{\frac{ V \; I \; \%\eta \; PF \; 1.73 }{ 746 } }$$