The direct current is necessary for food of the majority of radio-electronic devices. At the same time electric generators and power supply networks are suppliers of alternating current. The network power supply which to collect independently is necessary for transformation.
It is required to you
- - transformer;
- - lamp or semiconductor diodes;
- - throttle;
- - electrolytic condensers;
- - measuring devices;
- - accessories to soldering and installation.
Instruction
1. The network power supply consists of three main parts: the transformer, the rectifier and the smoothing filter. If you need tension approximately equal network, then it is possible to do also without transformer, having just straightened power supply network tension. But such power supply is dangerous as at its exit there will be a full mains voltage. The galvanic outcome with the power supply network in this case is absent. Besides the transformer allows to receive the necessary tension which can be higher or lower network and also several tension that sometimes too happens it is necessary.
2. Pick up the transformer giving tension necessary for you at the exit. At the same time primary winding is calculated on tension of the current source (generator or the power supply network) which is available for you.
3. Connect to an output winding the semiconductor diode as it is shown on the scheme. You receive the simplest one-half-period rectifier. At its exit — the pulsing current which frequency is twice lower than the power supply network frequency as at you the second half-cycle vanishes. But for food of some electronic schemes quite we accept such option.
4. Much more perfect are two-half-period rectifiers at which the frequency of pulsations of current is equal to the frequency of the feeding power supply network. In this case both half-cycles of supply voltage become straight. If your transformer has an output winding with an average point, you can assemble the device according to scheme 2.
5. Can happen that you have the transformer without average point of an output winding, and the fed device is sensitive to current pulsations. In this case you can assemble the two-half-period rectifier according to the scheme of the bridge.
6. At the output of any rectifier you receive not the constant, and pulsing tension. It needs to be smoothed. LC or RC filters are for this purpose used. They consist of high-capacity electrolytic condensers between which the throttle is included. Sometimes the throttle can be replaced with the powerful resistor. Surely equip the power supply with such filter.