What Is the Reading on a Multimeter When You Have a Short

Download Commodity

Download Article

The labels on a multimeter can seem like their own language to a layman, and fifty-fifty people with electrical experience may need a helping paw if they encounter an unfamiliar multimeter with an offbeat abbreviation system. Fortunately, information technology won't take long to translate the settings and understand how to read the scale, so you lot tin get back to your work.

1. one

   Test Ac or DC voltage. In general, V indicates voltage, a squiggly line indicates alternating electric current (found in household circuits), and a straight or dashed line indicates direct current (found in most batteries). The line can appear adjacent to or over the letter.^[1]

   • The ability coming from most household circuits is AC. Yet, some devices may catechumen the ability to DC through a transistor, so check the voltage label before you test an object.^[ii]
   • The setting for testing voltage in an AC excursion is typically marked V~, ACV, or VAC.
   • To exam voltage on a DC circuit, set the multimeter to V–, Five---, DCV, or VDC.

2. ii

   Set the multimeter to measure electric current. Because current is measured in amperes, it is abbreviated A. Cull direct electric current or alternating current, whichever the circuit you are testing is fabricated for. Analog multimeters typically exercise not have the power to exam current.

   • A~, ACA, and AAC are for alternating electric current.
   • A–, A---, DCA, and ADC are for direct current.

   Advertisement

3. 3

   Notice the resistance setting. This is marked by the Greek letter omega: Ω. This is the symbol used to denote ohms, the unit of measurement used to measure resistance. On older multimeters, this is sometimes labeled R for resistance instead.

4. 4

   Use DC+ and DC-. If your multimeter has this setting, keep information technology on DC+ when testing a straight current. If you aren't getting a reading and suspect yous've got the positive and negative terminals attached to the incorrect ends, switch to DC- to right this without having to suit the wires.^[3]

5. 5

   Understand other symbols. If you lot're not sure why there are multiple settings for voltage, electric current, or resistance, read the troubleshooting section for information on ranges. Besides these basic settings, most multimeters accept a couple additional settings. If more than one of these marks is next to the aforementioned setting, it may do both simultaneously, or you may demand to refer to the manual.

   • ) ) ) or a like serial of parallel arcs indicates the "continuity exam." At this setting, the multimeter will beep if the two probes are electrically connected.^[4]
   • A right-pointing arrow with a cantankerous through information technology marks the "diode test," for testing whether i-fashion electric circuits are connected.^[5]
   • Hz stands for Hertz, the unit for measuring the frequency of AC circuits.^[6]
   • –|(– symbol indicates the capacitance setting.

6. 6

   Read the port labels. About multimeters take three ports or holes. Sometimes, the ports volition be labeled with symbols that friction match the symbols described above. If these symbols are unclear, refer to this guide:

   • The black probe always goes into the port labeled COM for common (also called the ground. (The other finish of the black lead always connects to the negative concluding.)
   • When measuring voltage or resistance, the crimson probe goes into the port with the smallest electric current label (ofttimes mA for milliamps).^[7]
   • When measuring current, the cerise probe goes into the port labeled to withstand the amount of expected current. Typically, the port for low-electric current circuits has a fuse rated to 200mA while the high-current port is rated to 10A.^[viii]

   Advertisement

1. i

   Find the correct scale on an analog multimeter. Analog multimeters take a needle backside a glass window, which moves to indicate the result. Typically, there are three arcs printed behind the needle. These are three different scales, each of which is used for a unlike purpose:^[9]

   • The Ω scale is for reading resistance. This is typically the largest scale, at the elevation. Unlike the other scales, the 0 (zero) value is on the far right instead of the left.
   • The "DC" scale is for reading DC voltage.
   • The "AC" calibration is for reading Air conditioning voltage.
   • The "dB" scale is the least used pick. See the end of this section for a cursory explanation.

2. 2

   Make a voltage scale reading based on your range. Look carefully at the voltage scales, either DC or AC. There should exist several rows of numbers beneath the scale. Check which range you have selected on the dial (for instance, 10V), and await for a corresponding label next to i of these rows. This is the row you should read the event from.

3. 3

   Approximate the value between numbers. Voltage scales on an analog multimeter work simply similar an ordinary ruler. The resistance scale, however, is logarithmic, meaning that the same distance represents a dissimilar change in value depending on where you are on the scale. The lines between two numbers still represent even divisions. For example, if there are three lines between "l" and 70," these represent 55, threescore, and 65, even if the gaps between them look different sizes.

4. iv

   Multiply the resistance reading on an analog multimeter. Wait at the range setting that the dial of your multimeter is fix to. This should give yous a number to multiply the reading by. For example, if the multimeter is prepare to R x 100 and the needle points to 50 ohms, the actual resistance of the circuit is 100 ten 50 = five,000.

5. 5

   Discover out more near the dB scale. The "dB" (decibel) calibration, typically the lowest, smallest ane on an analog meter, requires some additional preparation to use. It is a logarithmic calibration measuring the voltage ratio (also called proceeds or loss).^[10] The standard dBv scale in the US defines 0dbv as 0.775 volts measured over 600 ohms of resistance, but at that place are competing dBu, dBm, and fifty-fifty dBV (with a majuscule 5) scales.^[11]

   Advertisement

1. 1

   Set the range. Unless you have an auto-ranging multimeter, each of the basic modes (voltage, resistance, and current) has several settings to cull from. This is the range, which y'all should ready earlier you attach the leads to the excursion. Start out with your best guess for the value which is just to a higher place the closest result. For instance, if you lot expect to measure effectually 12 volts, gear up the meter to 25V, not 10V, assuming those are the ii closest options.^[12]

   • If you lot take no idea what current to expect, set information technology to the highest range for your starting time attempt to avoid damaging the meter.
   • Other modes are less probable to impairment the meter, but consider the lowest resistance setting and the 10V setting your default.^[13]

2. 2

   Adjust to "off the scale" readings. On a digital meter, "OL," "OVER," or "overload" means y'all demand to select a higher range, while a result very close to zero means a lower range will give more than accuracy. On an analog meter, a needle that stays notwithstanding usually means you need to select a lower range. A needle that shoots to the maximum ways you need to select a college range.

3. 3

   Disconnect the power before measuring resistance. Turn off the power switch or remove the batteries powering the excursion in order to become an authentic resistance reading.^[14] The multimeter sends out a current to measure the resistance, and if additional current is already flowing, this will disrupt the result.

4. iv

   Measure current in series. To measure out electric current, you'll need to form one circuit that includes the multimeter "in series" with the other components. For case, disconnect i wire from a bombardment terminal, so connect one probe to the wire and 1 to the battery to close the excursion again.

5. 5

   Measure out voltage in parallel. Voltage is the change in electric energy across some part of the circuit. The circuit should already exist airtight with current flowing, then the meter should accept the two probes placed at different points on the excursion to connect it "in parallel" with the circuit. This must be done carefully to avoid discrepancy.

6. vi

   Calibrate ohms on an analog meter. Analog meters have an additional dial, used to adjust the resistance calibration and typically marked with an Ω. Earlier making a resistance measurement, connect the two probe ends to each other. Plow the dial until the ohm scale reads zero, to calibrate information technology, then conduct your actual examination.^[15]

   Advertisement

Add together New Question

• Question

  What are some basics for reading a multimeter?

  

  Jesse Kuhlman is a Main Electrician and the Owner of Kuhlman Electrician Services based in Massachusetts. Jesse specializes in all aspects of dwelling/residential wiring, troubleshooting, generator installation, and WiFi thermostats. Jesse is besides the author of four eBooks on home wiring including "Residential Electrical Troubleshooting" which covers basic electrical troubleshooting in residential homes.

  

  Chief Electrician

  Expert Reply

  The best way to think most amperage and voltage is to recollect of a water hose. Voltage is the water pressure and amperage is the size of the hose. The larger the hose, the more than amperage.

Enquire a Question

200 characters left

Include your email accost to become a message when this question is answered.

Submit

Advert

Video

• If the needle of an analog multimeter points beneath nil fifty-fifty at the everyman range, then your "+" and "-" connectors are probably backwards. Switch the connectors and take another reading.

• If there is a mirror backside the needle of your analog multimeter, plough the meter left or right and then that the needle covers its own reflection for ameliorate accurateness.

• If the multimeter ceases to work, then you should test information technology to determine the trouble.

• If you lot are having problem reading a digital multimeter, refer to the transmission. By default, it should display the numeric upshot, but there could as well be settings that display bar graphs or other forms of data display.

• The initial measurement will fluctuate while measuring AC voltage, simply this will stabilize to an accurate reading.^[16]

• If you're having problem remembering the deviation between voltage and amperage, picture a h2o hose. The voltage is the h2o pressure level that'south moving through the hose, and the amperage is the size of the hose, which controls how much water can move through at once.^[17]

Advert

• If yous fail to select a college range than the expected output of your circuit or battery, and so the reading could damage your multimeter. Analog multimeters tend to be much more fragile than digital multimeters, while auto-ranging digital multimeters are sturdiest of all.

Advertisement

Almost This Commodity

Article Summary X

To read a multimeter on an AC system, you'll need to locate the numbers and symbols on your circuit organization. On an Ac excursion, for instance,5 stands for "voltage," while a squiggly line indicates the alternating current. If you want to test a DC circuit, switch the setting on your multimeter to VDC or DCV. Alternatively, if you accept an analog multimeter, you'll need to cheque the numbers that the needle is pointing to beneath the glass screen. You can as well refer to your user's guide for specific information nigh your multimeter settings. For tips on how to conform for off the scale readings, keep reading!

Did this summary assist you?

Cheers to all authors for creating a page that has been read 750,644 times.

Did this commodity help yous?

sanabriagaill1942.blogspot.com

Source: https://www.wikihow.com/Read-a-Multimeter

Bagikan Artikel ini