Advice 1: How to determine the value of capacitor

Not always on the capacitor is directly specified capacity in units derived from Farad. Often to reduce the size of the marking, the manufacturers resorted to the use of abbreviations and codes. In the electric diagrams in the notation of capacity there are also special reductions.
How to determine the value of capacitor
Instruction
1
If you electric concept, made under the old standard, the designation of the capacity in which there is a comma regardless of whether the fractional part is zero, always expressed in microfarads. For example:0,015;
50,0.If the comma marking no, the capacity of the capacitor expressed in picofarads, for example:5100;
200.
2
In modern schemes the capacity of the capacitor isexpressed in microfarads, always abbreviated "MK" (not "IFF"). Comma may be present or may not have. For example:200 MK;
0.01 MK.Denote capacitance expressed in picofarads, the transition to the new standard have not changed.
3
A slightly different way of labeling the containers used for the labeling of the buildings themselves capacitors. The designation "pF" or a complete absence of the name of the unit suggests that the capacitance is expressed in picofarads. Microfarad denoted using the abbreviation "IFF". Nanofarad represent the Russian letter "h" or Latin n. If the part numbers are up to that letter, and the other part - after the letter is equivalent to a comma. For example the code "4n7" is read as "4.7 nanofarads".
4
Miniature condenserx (including form factor SMD) capacity denoted by means of special codes consisting of numbers and letters. When decoding, please refer to the document located at the link given in the end of the article.
5
Remember that capacity is not the only characteristic of the capacitor. When used in pulse circuits such important parameter as the equivalent series resistance in high frequency circuits - the parasitic inductance. Often the case of the device is not marked neither, and these parameters must be measured. It is also important to know the polarity of the inclusion of the capacitorif it is electrolytic, and its nominal voltage. Imported condenser near the negative terminal has a long strip of hyphens, but at home near the positive terminal has a plus sign. A special method of marking is applied on the capacitorx type K50-16: both signs of polarity (plus and minus) stamped on the plastic bottom of the item.

Advice 2: How to find the value of the resistor

Designation of the values of resistors on the schematics and the components are performed according to different standards. In addition, some resistors for the encoding numbers are used instead of numbers, the color of the ring.
How to find the value of the resistor
Instruction
1
On the wiring diagram the resistor are given without specifying the unit of measurement is generally expressed in ohms. For example, the number 200 means 200 Ohms. If after the numbers located lowercase letter K, we are talking about Kromah: 250 to 250 is file com. If the old schemes unit of measurement in the designation is absent, and the number in addition to a part is and the fractional, the value is expressed in megohms: 10,0 stands for 10 MW. On new schemes to do this, use the capital letter M: 5 M means 5 Mω. Capital letter G replaces the unit dimension D (gigaom). These resistors are rare, mainly in radiation equipment based on ionization chambers.
2
On the resistors instead of using the name Om unit uses either the Latin capital letter R or a capital Greek letter Ω (omega"). Kilome are denoted by the capital letter K, megohms - capital letter M, higami - uppercase Russian letter G Latin or G. the Numbers located before and after the letters is the equivalent of digits after the decimal point. For example, 2R5 - 2.5 Ohm, 120K - 120 ohms, 4М7 - 4.7 Mω. Less the resistance value is specified using the conventional notation of units, for example, 10 kω.
3
Using the color rings on the resistors are coded with different numbers. The following colors are used: black - 0, brown - 1, red - 2, orange - 3, yellow - 4, green - 5, blue - 6, violet - 7, grey - 8, white - 9. These bands may be three or four. All of them, except the last, represent numbers, and the last is number of zeros following those digits. The resulting number expresses the resistance in ohms, which can be converted to more convenient units.
4
If after them after a short period of located gold band, the resistor has a tolerance of 5%. The silver band tells about the tolerance of 10%, and if it does not exist, the tolerance on resistance equal to 20%. Countdown guide strips on the side opposite the strip, symbolizing tolerance.
5
The resistor on which the marking is absent, the resistance can be measured. To do this, power off the circuit, discharge the capacitors, confirm with a voltmeter that they are really discharged, and then desolder one lead of the resistor and connect it to an ohmmeter. Select the limit at which resistance is displayed most accurately. After reading the readings, disconnect the ohmmeter and solder the disconnected output back.

Advice 3: How to determine the efficiency of the condenser

There are two main types of capacitors faults: open circuit and breakdown. In addition, the breakdown may be partial (then it is a leak), or occur only at a certain voltage). Also a capacitor may lose capacitance or he may increase the equivalent series resistance.
How to determine the efficiency of the condenser
Instruction
1
Any check capacitor is fully discharged, both its output should be disconnected from any other circuits. Neglect of this rule in danger of electric shock and equipment damage.
2
Connect the ohmmeter capacitor (electrolytic is in the right polarity). First, through the device should go current, but after charging it needs to stop. The small capacitors it turns so fast that the ohmmeter does not have time to react. Help penlight batteries, connected in series with the headphones. Such a probe must be connected to the capacitor several times. If the click will be heard only when you first connect, the device is working properly. If the current continues to flow, there is a breakdown, does not occur even if charge is open.
3
To detect intermittent breakdowns, which manifests itself only at an operating voltage, make the circuit of the voltage source, equal to the condenser, the milliammeter and the load, limiting the current to a safe value. Electrolytic capacitor connect in the correct polarity. Current must first occur, and then rapidly decrease to zero. Turning off voltage, discharge the capacitor.
4
Leak check the capacitor, charging it up to operating voltage, and then disconnect from the power source. After some time, check the voltage on the capacitor with a voltmeter. Electrolytic capacitor should hold a charge for at least half an hour, and any other - at least a few hours. After checking the discharge component.
5
The capacity check, perform by using a bridge device. Select such a limit, which by rotating the handle of the bridge the sound disappears. Find the location of the pointer in which the sound disappears completely, and read the capacitance value on the scale. Compare it with the nominal.
6
To check the equivalent series resistance, use a generator operating at a frequency at which the capacitive resistance can be neglected. The generator must produce a sine wave voltage to the voltmeter and the AC voltmeter worked with the least possible error. Divide the voltmeter readings of the milliammeter (pre-translated in the SI system), and you will receive the equivalent series resistance of the capacitor in ohms. The smaller it is, the better.
Note
Do not touch the chain under tension, as well as the conclusions of the charged capacitor. To discharge use no jumper, as the load limiting discharge current to a safe value.
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