## Saturday, July 6, 2024

How To Make 220V to 12V 60A Battery Charger | Full Bridge Rectifier Circuit

How to Calculate the Charging Time and Charging Current for Battery Charging?

Easy Battery Charging Time and Battery Charging Current Formula for Batteries. (With Example of 120Ah Battery).

In the following simple tutorial, we will show how to determine the suitable battery charging current as well as How to calculate the required time of battery charging in hours with a solved example of 12V, 120 Ah lead acid battery.

Related Posts: How to Calculate the Right Size Battery? Battery Bank Size Calculator

Below are the given formulas for required battery charging time in hours and needed charging current in amperes as follows.

Example:

Calculate the suitable charging current in Amps and the needed charging time in hrs for a 12V, 120Ah battery.

Battery Charging Current:

First of all, we will calculate charging current for 120 Ah battery. As we know that charging current should be 10% of the Ah rating of battery.

Therefore,

Charging current for 120Ah Battery = 120 Ah x (10 ÷ 100) = 12 Amperes.

But due to some losses, we may take 12-14 Amperes for battery charging purpose instead of 12 Amps.

Related Posts

Battery Capacity Rating Calculator Formula and Equations

Battery Life Calculator (Formula and Equations)

Battery Charging Time:

Suppose we took 13 Amp for charging purpose,

then,

Charging time for 120Ah battery = 120 ÷ 13 = 9.23 Hrs.

But this was an ideal case…

Practically, it has been noted that 40% of losses occur in case of battery charging

How to Find the Base, Collector, Emitter, Direction & Condition of Transistor by Multimeter

How to remember the direction of PNP and NPN Transistor & Pin Identification, Check if it is Good or Bad.

The following basic tutorial based on using digital (DMM) or analog (AVO) multimeter will help you to:

Remember the direction of NPN and PNP Transistors

Identify the Base, Collector & Emitter of a Transistor

Check a transistor if it is Good or Bad.

Related Posts:

Bipolar Junction Transistor (BJT) | Construction, Working, Types & Applications

Types of Transistors – BJT, FET, JFET, MOSFET, IGBT & Special Transistors

PNP = Pointed In

NPN = Not Pointed In.

If you think that is a little bit complex, then try the more simple one as follows.

PNPNPN

P = Points N = Never

N = IN P = Points

P = Permanently N = iN

Now let’s move to the step by step tutorial to know how to check and test a transistor?

Test a Transistor using Digital Multimeter in Diode or Continuity Mode

To do so, follow the instructions given below.

Remove the transistor from the circuit i.e. disconnect the power supply across the transistor which has to be tested. Discharge all the capacitors (by shorting the capacitor leads) in the circuit (If any).

Set the meter to “Diode Test” Mode by turning the rotary switch of the multimeter.

Connect the Black (common or -Ve) test lead of the multimeter to the 1st terminal of the transistor and Red (+Ve) test lead to the 2nd terminal (Figure below). You have to perform 6 tests by connecting the Black (-Ve) test lead and Red (+Ve) test lead to 1 to 2, 1 to 3, 2 to 1, 2 to 3, 3 to 1, 3 to 2 respectively by just replacing the multimeter test leads or reverse the transistor terminals to connect, test, measure and note the reading in the table (shown below). Numbers in Red colors are Red Test Lead and numbers in Black are connected to Black (-Ve) test lead of multimeter.

Test, measure and note the display reading shown in the multimeter in the table below.

We have the following data from the table given below.

Out of 6 tests, we got data and results only on two tests i.e. points 2 to 1 and 2 to 3. Where we got at points 2 to 1 is 0.733 VDC and 2 to 3 is 0.728 VDC. Now, we can easily find the type of transistor as well as their collector, base and emitter.

Point 2 is Transistor Base in BC55 Transistor.

BC 557 is a PNP Transistor where the 2nd (middle terminal is base) connected to Red (+Ve) test lead of the multimeter.

At all, Terminal 1 = Emitter, Terminal 2 = Base, and Terminal 3 = Collector (BC 557 PNP Transistor) because, the test result for 2-1 = 0.733 VDC and 2-3 = 0.728 VDC, i.e. 2-1 > 2-3.

Finding BASE of Transistor:

As mentioned in the above tutorial, the common number found in the tests above is base. In our case, 2nd terminal is Base and 2 is common out of 1-2 and 2-3.

2nd Method using DMM to find the Base of the Transistor.

If you follow the same pattern and connecting method of multimeter leads and transistor terminals one by one in the figure shown above, in fig “c” and “d”, The Red (+Ve) test lead is connected to the middle one i.e. 2nd terminal of lead and the Black (-Ve) test lead is connected to the 1st one terminal of transistor.

Again, The Red (+Ve) test lead is connected to the middle one i.e. 2nd terminal of lead and the Black (-Ve) test lead is connected to the 3rd one terminal of transistor and multi meter shows some reading i.e. 0.717 VDC & 0.711 VDC respectively in the case of BC 547 NPN.

The common lead is 2nd one connected to Red (+Ve) test lead (i.e. P and yes, the other two leads are N) which is base. The case is reversed in the case of the BC 557 PNP transistor.

NPN or PNP?

It's simple. If the Black (-Ve) test lead of the multimeter is connected to the base of the transistor (2nd terminal in our case), then it is PNP transistor, and when Red (+Ve) test lead is connected to the base of the terminal, It is NPN transistor.

Related Posts:

Difference Between NPN and PNP Transistor

Difference Between BJT and FET Transistors

Emitter or Collector?

EB (Emitter – Base) forward bias is greater than CB (Collector – Base) i.e. EB > CB in PNP Transistor e.g. BC557 NPN. Hence, It is a PNP Type Resistor. In NPN Transistor, BE (Base – Emitter) forward bias is greater than BC (Base – Collector) i.e. BE > BC, e.g. BC 547 PNP.

Here is the conclusion.

Point 2 is Transistor Base in BC547 Transistor

BC 547 is a NPN Transistor where the 2nd (middle terminal is base) is connected to Red (+Ve) test lead of multimeter.

At all, Terminal 1 = Emitter, Terminal 2 = Base, and Terminal 3 = Collector (BC 547 NPN Transistor) because, the test result for 1-2 = 0.717 VDC and 2-3 = 0.711 VDC, i.e. 1-2 > 2-3.

Check a Transistor using Analog or Digital Multimeter in Ohm (Î©) Range Mode:

Disconnect the power supply to the circuit and remove the transistor from the circuit.

Rotate the selector switch and put the Multimeter knob in Ohm Range (OHM)

Connect the Black (common or -Ve) test lead of the multimeter to the 1st terminal of the transistor and Red (+Ve) test lead to the 2nd terminal (Figure 1 (a). (You have to perform 6 tests by connecting the Black (-Ve) test lead to 1 to 2, 1 to 3, 2 to 1, 2 to 3, 3 to 1, 3 to 2 respectively by just replacing the multimeter test leads or reverse the transistor terminals to connect, test, measure and note the reading in the table (shown below). (Numbers in Red colors show the transistor leads connected to the Red (+Ve) test lead of multimeter and the numbers in black colors show the transistor leads connected to the Black (-Ve). ) test lead of multimeter (Better explanation in the table & fig below)

If the multimeter shows high resistance in both first and second tests by changing the polarity of either transistor or multimeter, as shown in Fig 1 (a) and (b). (Note that, the result will be shown only for 2 tests out of 6 as mentioned above). i.e. In our case, the 2nd terminal of the transistor is BASE, because it shows high resistance in both tests of 2 to 3 and 3 to 2 where Red (+Ve) test lead of the multimeter is connected to the 2nd terminal of the transistor. In other words, the common number in tests is Base which is 2 out of 1, 2 and 3.

PNP or NPN?

Now, it is a NPN transistor because, it shows reading only when the RED (+Ve) test lead (i.e. P terminal where P = Positive) is connected to the Base of the transistor (See fig below). If you do the reverse, i.e. Black (-Ve) test lead (i.e. N = where N = Negative) of multimeter connected to the transistor terminal in sequence of (1 to 2 and 2 to 3) and shows reading in both tests as above, The 2nd Terminal is still BASE , but the transistor is PNP (see fig below).

Testing a Transistor using Digital Multimeter in the Transistor or hFE or Beta Mode

hFE also known as beta is dc gain stands for “Hybrid parameter forward current gain, common emitter” used to measure the hFE of a transistor which can be found by the following formula.

hFE = Î²DC = IC/IB

It can also be used to check a transistor and its pin terminal as shown in fig 1.

To check a transistor in hFE mode, there are 8 pins slot in the multimeter indicated by PNP and NPN as well as E C B (Emitter, Collector and Base). Simply put the three pins of transistor in the multimeter slot one by one in different slots i.e. ECB or CBE (Rotary knob should on hFE mode).

If they display reading (It would be the hFE reading of transistor), In our example, We used BC548 Transistor which shows the beta value of 368 (CBE position) the current position on the C, B, E slot are the exact terminals of transistor i.e. collector, base and emitter) and transistor is in good position, otherwise, replace with new one.

How To Make 220V to 12V 60A Battery Charger | Full Bridge Rectifier Circuit

How to Calculate the Charging Time and Charging Current for Battery Charging?

Easy Battery Charging Time and Battery Charging Current Formula for Batteries. (With Example of 120Ah Battery).

In the following simple tutorial, we will show how to determine the suitable battery charging current as well as How to calculate the required time of battery charging in hours with a solved example of 12V, 120 Ah lead acid battery.

Related Posts: How to Calculate the Right Size Battery? Battery Bank Size Calculator

Below are the given formulas for required battery charging time in hours and needed charging current in amperes as follows.

Example:

Calculate the suitable charging current in Amps and the needed charging time in hrs for a 12V, 120Ah battery.

Battery Charging Current:

First of all, we will calculate charging current for 120 Ah battery. As we know that charging current should be 10% of the Ah rating of battery.

Therefore,

Charging current for 120Ah Battery = 120 Ah x (10 ÷ 100) = 12 Amperes.

But due to some losses, we may take 12-14 Amperes for battery charging purpose instead of 12 Amps.

Related Posts

Battery Capacity Rating Calculator Formula and Equations

Battery Life Calculator (Formula and Equations)

Battery Charging Time:

Suppose we took 13 Amp for charging purpose,

then,

Charging time for 120Ah battery = 120 ÷ 13 = 9.23 Hrs.

But this was an ideal case…

Practically, it has been noted that 40% of losses occur in case of battery charging

How to Find the Base, Collector, Emitter, Direction & Condition of Transistor by Multimeter

How to remember the direction of PNP and NPN Transistor & Pin Identification, Check if it is Good or Bad.

The following basic tutorial based on using digital (DMM) or analog (AVO) multimeter will help you to:

Remember the direction of NPN and PNP Transistors

Identify the Base, Collector & Emitter of a Transistor

Check a transistor if it is Good or Bad.

Related Posts:

Bipolar Junction Transistor (BJT) | Construction, Working, Types & Applications

Types of Transistors – BJT, FET, JFET, MOSFET, IGBT & Special Transistors

PNP = Pointed In

NPN = Not Pointed In.

If you think that is a little bit complex, then try the more simple one as follows.

PNPNPN

P = Points N = Never

N = IN P = Points

P = Permanently N = iN

Now let’s move to the step by step tutorial to know how to check and test a transistor?

Test a Transistor using Digital Multimeter in Diode or Continuity Mode

To do so, follow the instructions given below.

Remove the transistor from the circuit i.e. disconnect the power supply across the transistor which has to be tested. Discharge all the capacitors (by shorting the capacitor leads) in the circuit (If any).

Set the meter to “Diode Test” Mode by turning the rotary switch of the multimeter.

Connect the Black (common or -Ve) test lead of the multimeter to the 1st terminal of the transistor and Red (+Ve) test lead to the 2nd terminal (Figure below). You have to perform 6 tests by connecting the Black (-Ve) test lead and Red (+Ve) test lead to 1 to 2, 1 to 3, 2 to 1, 2 to 3, 3 to 1, 3 to 2 respectively by just replacing the multimeter test leads or reverse the transistor terminals to connect, test, measure and note the reading in the table (shown below). Numbers in Red colors are Red Test Lead and numbers in Black are connected to Black (-Ve) test lead of multimeter.

Test, measure and note the display reading shown in the multimeter in the table below.

We have the following data from the table given below.

Out of 6 tests, we got data and results only on two tests i.e. points 2 to 1 and 2 to 3. Where we got at points 2 to 1 is 0.733 VDC and 2 to 3 is 0.728 VDC. Now, we can easily find the type of transistor as well as their collector, base and emitter.

Point 2 is Transistor Base in BC55 Transistor.

BC 557 is a PNP Transistor where the 2nd (middle terminal is base) connected to Red (+Ve) test lead of the multimeter.

At all, Terminal 1 = Emitter, Terminal 2 = Base, and Terminal 3 = Collector (BC 557 PNP Transistor) because, the test result for 2-1 = 0.733 VDC and 2-3 = 0.728 VDC, i.e. 2-1 > 2-3.

Finding BASE of Transistor:

As mentioned in the above tutorial, the common number found in the tests above is base. In our case, 2nd terminal is Base and 2 is common out of 1-2 and 2-3.

2nd Method using DMM to find the Base of the Transistor.

If you follow the same pattern and connecting method of multimeter leads and transistor terminals one by one in the figure shown above, in fig “c” and “d”, The Red (+Ve) test lead is connected to the middle one i.e. 2nd terminal of lead and the Black (-Ve) test lead is connected to the 1st one terminal of transistor.

Again, The Red (+Ve) test lead is connected to the middle one i.e. 2nd terminal of lead and the Black (-Ve) test lead is connected to the 3rd one terminal of transistor and multi meter shows some reading i.e. 0.717 VDC & 0.711 VDC respectively in the case of BC 547 NPN.

The common lead is 2nd one connected to Red (+Ve) test lead (i.e. P and yes, the other two leads are N) which is base. The case is reversed in the case of the BC 557 PNP transistor.

NPN or PNP?

It's simple. If the Black (-Ve) test lead of the multimeter is connected to the base of the transistor (2nd terminal in our case), then it is PNP transistor, and when Red (+Ve) test lead is connected to the base of the terminal, It is NPN transistor.

Related Posts:

Difference Between NPN and PNP Transistor

Difference Between BJT and FET Transistors

Emitter or Collector?

EB (Emitter – Base) forward bias is greater than CB (Collector – Base) i.e. EB > CB in PNP Transistor e.g. BC557 NPN. Hence, It is a PNP Type Resistor. In NPN Transistor, BE (Base – Emitter) forward bias is greater than BC (Base – Collector) i.e. BE > BC, e.g. BC 547 PNP.

Here is the conclusion.

Point 2 is Transistor Base in BC547 Transistor

BC 547 is a NPN Transistor where the 2nd (middle terminal is base) is connected to Red (+Ve) test lead of multimeter.

At all, Terminal 1 = Emitter, Terminal 2 = Base, and Terminal 3 = Collector (BC 547 NPN Transistor) because, the test result for 1-2 = 0.717 VDC and 2-3 = 0.711 VDC, i.e. 1-2 > 2-3.

Check a Transistor using Analog or Digital Multimeter in Ohm (Î©) Range Mode:

Disconnect the power supply to the circuit and remove the transistor from the circuit.

Rotate the selector switch and put the Multimeter knob in Ohm Range (OHM)

Connect the Black (common or -Ve) test lead of the multimeter to the 1st terminal of the transistor and Red (+Ve) test lead to the 2nd terminal (Figure 1 (a). (You have to perform 6 tests by connecting the Black (-Ve) test lead to 1 to 2, 1 to 3, 2 to 1, 2 to 3, 3 to 1, 3 to 2 respectively by just replacing the multimeter test leads or reverse the transistor terminals to connect, test, measure and note the reading in the table (shown below). (Numbers in Red colors show the transistor leads connected to the Red (+Ve) test lead of multimeter and the numbers in black colors show the transistor leads connected to the Black (-Ve). ) test lead of multimeter (Better explanation in the table & fig below)

If the multimeter shows high resistance in both first and second tests by changing the polarity of either transistor or multimeter, as shown in Fig 1 (a) and (b). (Note that, the result will be shown only for 2 tests out of 6 as mentioned above). i.e. In our case, the 2nd terminal of the transistor is BASE, because it shows high resistance in both tests of 2 to 3 and 3 to 2 where Red (+Ve) test lead of the multimeter is connected to the 2nd terminal of the transistor. In other words, the common number in tests is Base which is 2 out of 1, 2 and 3.

PNP or NPN?

Now, it is a NPN transistor because, it shows reading only when the RED (+Ve) test lead (i.e. P terminal where P = Positive) is connected to the Base of the transistor (See fig below). If you do the reverse, i.e. Black (-Ve) test lead (i.e. N = where N = Negative) of multimeter connected to the transistor terminal in sequence of (1 to 2 and 2 to 3) and shows reading in both tests as above, The 2nd Terminal is still BASE , but the transistor is PNP (see fig below).

Testing a Transistor using Digital Multimeter in the Transistor or hFE or Beta Mode

hFE also known as beta is dc gain stands for “Hybrid parameter forward current gain, common emitter” used to measure the hFE of a transistor which can be found by the following formula.

hFE = Î²DC = IC/IB

It can also be used to check a transistor and its pin terminal as shown in fig 1.

To check a transistor in hFE mode, there are 8 pins slot in the multimeter indicated by PNP and NPN as well as E C B (Emitter, Collector and Base). Simply put the three pins of transistor in the multimeter slot one by one in different slots i.e. ECB or CBE (Rotary knob should on hFE mode).

If they display reading (It would be the hFE reading of transistor), In our example, We used BC548 Transistor which shows the beta value of 368 (CBE position) the current position on the C, B, E slot are the exact terminals of transistor i.e. collector, base and emitter) and transistor is in good position, otherwise, replace with new one.