# How to connect a car battery or DC Circuits

In this article we will teach you how to connect a car battery. Polarity tester electronics circuit that will easily test the polarity of a DC source. Components needed and  connection diagram is given below. Is is easy to test the polarity of a circuit’s point whether it is positive or negative. In this way you can avoid the problem of wrong connection. Polarity checker circuit   is very easy, just follow the diagram while making it.

Every DC source has two terminals

1.  Positive
2. Negative

The conventional current always flows from positive battery terminal to negative battery terminal. The vice versa is wrong connection. Therefore we must have to check specific terminal because Only correct connection according to polarity will ensure correct functionally of the circuit. If the connections are wrong way then circuit will not only function improperly but can also become the cause of damaging the circuit. Wrong connection will burn main components of a device such as power ic etc. So it is very important to ensure correct polarity during connection. This article explain a simple project with the help of this circuit you can check polity of a battery very easily.

For learning how to make it practically plz watch video

## How to build Polarity Checker circuit

This circuit can be made with two ways: with Diode and LEDs and without Diodes. We make it with both methods. So first of all we make it with without diodes.

#### Polarity circuit with Only LEDs and resistor

Components Required

1. Green LED
2. Red LED
3. Buzzer 6v
4. 1k Resistor
5. Red and Black Nobs

In this project Buzzer is optional. you can make this circuit without buzzer.You can make it without PCB (circuit board) because few components are used in the project.
Note: Use buzzer directly with nobs wires because because buzzer takes little more power. Buzzer ring only when the connection are correct. i have used 6v buzzer because it will ring from 3 to 24 volts easily.

### Polarity circuit with Diodes and LED’s

In this circuit we have used diode and 1 resistor

1. Diodes 4
2. LED diodes 2 (1 green and 1 RED)
3. Resistor 1k

In this circut diagram, 1k resistors is used while all diodes are IN4007 and two LEDs RED and green are used. As a Leads you can use multi-meter leads.

You can use PCB or make it without PCB it depends on your desire any how PCB can increase the efficiency of a circuit. The video which i have uploaded on you tube represents this circuit with PCB.