The circuit was designed to create a spare and reserve power source with
 the use of batteries during the absence of power from the mains.
- BD139 – NPN power transistor used for driver stages in hi-fi amplifiers and television circuits because of its low voltage at 80 V maximum and high current at 1.5 A maximum.
- Bridge Rectifier – also known as bridge rectifier which has four diodes arranged in a bridge configuration where the output voltage has the same polarity with either polarity of the input voltage.
- 1N4002 – a 1.0 Amp Silicon rectifier with voltage range of 50 to 1000 Volts and possessing features such as guaranteed high temperature soldering, high current capability, diffused junction, low reverse leakage, utilizes void-free molded plastic technique for low cost construction, and carries Underwriters Laboratory Flammability Classification of 94V-0 by its plastic package.
One of the main components in the construction of this circuit is the 
transformer which is rated with 230V/10V with a given current of 0.5A. 
It will handle the transfer of electrical energy from one circuit to 
another via inductive conductors or windings. Other components include a
 bridge rectifier and an electrolytic capacitor. This will be followed 
by an 8V2 Zener diode rated at 0.4W, which provides the regulation of 
voltage in the transistor as it is connected in series with the base to 
produce a constant output voltage of 7.5 V.
Battery Circuit for Backup and Standby Operation
 To produce the desired 7.5 V, there are five batteries used in this 
circuit with 1.5 V each, in series with diode D7. This voltage is 
hanging across the output terminals, which takes over in case of failure
 in the main supply. The power supply will be reduced to 7 V due to the 
voltage drop across D7. The presence of resistor R3 performs an 
additional operation where it drops the charging of dry cells or storage
 battery, when it stops working with the main supply. To obtain the 
actual resistance of R3, the voltage potential difference between the 
battery and the Zener diode D6 is divided by the reliable current drop 
which measures around 0.7 mA.

The circuit of 7V backup battery is widely applied in several uninterruptible power supplies that efficiently function in times of power outage. Some models are incorporating the use of Lithium Ion and NiCd types of batteries. The most advantage feature that the circuit brings is providing backup power for emergency and important loads. Other models are created with high power capability to support high power applications.

The circuit of 7V backup battery is widely applied in several uninterruptible power supplies that efficiently function in times of power outage. Some models are incorporating the use of Lithium Ion and NiCd types of batteries. The most advantage feature that the circuit brings is providing backup power for emergency and important loads. Other models are created with high power capability to support high power applications.
 



 
 
 
 
0 comments:
Post a Comment