Tip 1: How to determine the resistance of the resistor

To determine the resistance of the resistor , easier and safer just to measure it with an ohmmeter or multimeter.However, this method is not always available, beginning with the elementary lack the necessary device, ending the physical inaccessibility of parts.In addition, prior to measuring the resistance of the resistor it must vypayat from the scheme, but this is not always possible.In this case, will help define the resistance of the resistor on its labeling.
you need
  • resistor, ohm meter, Multimeter, Magnifier.
Guide
1
easiest way to determine the resistance resistor - learn about it from the documentation.If the resistor is purchased as a separate item, get supporting documents (invoices, warranty card, etc.).Look for them in the denomination resistor .Most likely, the resistance will be listed next to the name of details, such as a resistor of 4.7 K. In this case, the number indicates the nominal value of the resistor , and letter (s) - a unit of measurement.Options K,
K, ohms, ohm, Com, whom kiloomam.Analogichnye designations correspond with the letter "M" instead of "to" - megohms.If the letter "m" is lowercase (small), then this corresponds theoretically milliohms.However, in practice, these resistors are not usually sold, and made yourself a few turns of special wire.Therefore, combined with the letter "m" can be attributed to megohms (in non-standard cases, better yet specified) The absence of number after the unit or the presence of the word "Om" or "th" means an ohm.(in practice may mean that the seller does not have a unit of measurement).
2
If the resistor is part of the electrical (electronic) devices, remove the wiring diagram of the device.If the scheme is not, try to find it on the Internet.Locate the diagram corresponding resistor.Resistors are denoted by small rectangles with lines coming out of the short sides.Inside the rectangle can be positioned dash (indicate capacity).Near the designation resistor (rectangle) is generally in the letter R and a number indicating the sequence number resistor in the circuit, for example, R10.After marking resistor indicated its face value (to the right or below).If resistance resistor is omitted, look in the lower part of the scheme - sometimes resistor values ​​(grouped by values) are there.
3
If you have an ohmmeter or multimeter, you simply connect the device to the terminals of the resistor and record the readings.Multimeter pre switch to resistance measurement.If the ohmmeter "rolls" or on the contrary, shows a very small value, set it to the appropriate range.If the resistor is part of the scheme, the pre vypayat it, otherwise the reading will certainly be incorrect (lower).
4
Denomination resistor can also be identified by its label.If the denomination consists of two numbers and one letter (typical of the old "Soviet" parts), use the following rule:
letter put in place the decimal point and represents multiple consoles: K - kilohms;
M - Mega;
E - units, ie,in this case, the denomination Om.Esli resistor - an integer, the corresponding letter is placed at the end of the notation (69K = 69 ohms).If resistance resistor less than one - the letter is placed before the number (M15 = 0.15 MW = 150 ohms).The fractional denominations letter is located between the numbers (9E5 = 9.5 ohm).
5
to indicate a three-digit, remember this simple rule: the first two numbers is necessary to add as many zeros as indicated by the third digit.For example, 162, 690, 166 is interpreted as follows: 162 = 16'00 Ohm = 1.6 kW;
690 = 69 '= 69 ohm ohms;
16'000000 = 166 ohms = 16 megohms.
6
If the value of the resistor marked with colored strips, turn (or rotate) so as to separate (separated by three) strip is on the right.Then, taking advantage of the table below to match colors, turn color strips in numbers: - Black - 0;
- brown - 1;
- red - 2;
- orange - 3;
- yellow - 4;
- green - 5;
- Blue - 6;
- purple - 7;
- Grey - 8;
- White - 9.Poluchiv three-digit number, use the rules described in the previous paragraph.For example, if the color of the three strips in the following order, that is, from left to right (red - 2, orange - 3, yellow - 4), we obtain the number 234, which corresponds to the nominal value of 230,000 ohms = 230 ohms.Incidentally, the above table is very easy to remember.The order corresponds to the average color of the rainbow, and color to the extreme end of the list become lighter.

Tip 2: How to determine the value of the resistor

Determine denomination (resistance) resistor , attaching to it an ohmmeter.If no ohmmeter, connect the resistor to a current source to measure the voltage across it and the current in the circuit.Then calculate its nominal value.In addition, the resistor can be calculated from color or special code.
How to determine the value of the resistor
you need
  • To determine the denomination take an ohmmeter, ammeter, voltmeter, tables decryption codes for nominal and by color.
Guide
1
Sizing resistor straight izmereniyami.Vozmite ohmmeter, connect it to the resistor by measuring its resistance.To properly set the sensitivity of the measurement device.If there is no ohmmeter, assemble an electric circuit comprising a resistor and an ammeter.In parallel resistor, connect a voltmeter.Then connect the circuit to the power supply.Learn the value of amperage, using the ammeter and voltage in volts, using a voltmeter.Divide the voltage on the current and get the nominal resistance of the resistor (R = U / I).
2
Sizing resistors codes or colored markirovkam.Vnimatelno consider resistor.If it is marked with three digits, the first two indicate the tens and units, and the third power of the number 10, which is necessary to multiply the number obtained from the code.For example, if the code is 873, it means that the number 87 is multiplied by 10 ^ 3.Get a nominal resistance of 87,000 ohms or 87 ohms.
Similarly, if a resistor marked four digits.The first three make up the numbers, and the last one - a power of 10 to which it multiply.For example, the resistor 3602 is 360 • 10² = 36 ohms.
3
In that case the resistor is marked with two numbers and one letter, use a special table marking SMD Resistor EIA, in which the first two digits correspond to the numerical value of resistance, and the letter - a power of 10. For example,to find the value of the resistor labeled 40S, multiply by 255 to get 10² resistance of 25.5 ohms.
4
If applied to the resistor colored marks or rings, take a table notation nominal resistance of color.The basic rule: start counting from the label at the first three represent the mantissa, the fourth - a power of 10, the fifth - tolerance of the resistor.To check, use a special program determining the value of the resistor.
Sources:
  • definition denominations resistors
Sources:
  • unit resistance com

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