Security for the wiring devices installation and repairs must be provided in all possible ways. It is necessary to exclude the light strikes and heavy shock. Do you agree? Before proceeding with elektrotochkami required voltage necessary to check that is performed by a multimeter.
We will tell you what is and how it works, this portable device that is used as a handyman and professional electricians. You will learn how to check your local AC mains voltage multimeter, as well as whether there is a supply voltage itself. Let us examine how with the help of current measurements are made.
For you we have described in detail the types of multimeters, led rules for their use. In order to optimize the perception of a difficult theme attached photo selections, charts, video.
The content of the article:
- Multimeters, testers and their varieties
- Domestic electrical network
- Safety precautions before work
- Legend multimeter
- Connecting the probe to the multimeter
- Measuring AC voltage in the socket
- Current measurement in the socket
- Measuring the voltage and current of the battery
- Conclusions and useful videos on the topic
Multimeters, testers and their varieties
Multimeter aka multitester, is a special device for measuring a wide variety of characteristics and parameters of the electrical network, as well as feeding it from the parts and elements.
The device is designed for on-site construction or repair could accurately determine:
- DC and AC voltage;
- AC and DC;
- resistance, capacitance, and more.
Besides the above parameters, multimeters equipped with additional measurement functions, which also makes it possible to test transistors "prozvanivat" wiring cable to the junction box and the wires coming out of it, check the function of diodes, etc.
image gallery
Photo of
Meter - a portable device that helps to timely detect broken wiring, check the efficiency of heating element and other electrical components in the circuit
Using a multimeter, the voltage can be checked at any point along the chain, connected to machines outlets, and battery charging check
For domestic use is not necessary to buy an option with an extended list of functions. Suffice multimeter capable to ring circuit to measure the resistance and voltage check
All multimeters presented for sale are divided into analog (with arrow display) and digital (electronic version)
Digital Multimeters preferred by professional electricians who need to record leaps in the power supply. Independent craftsmen easier and more convenient to work with a digital multimeter
During the execution of all operations for monitoring and measuring the electrical readings spent battery. All captured data is considered valid until the battery is discharged
One of the key characteristics of the testing device is an error. multimeters are suitable for domestic use with an accuracy of up to 3%
Significant feature of the meter is considered to safety class. CAT III multimeters suitable for wiring external control, CAT II testers are used to test household electrical circuit inside sq. / Home I CAT equipment is used in the control voltage network
Using a multimeter to solve everyday problems
Checking voltage and other characteristics of the network multimeter
Range control panel features
A switch or analog test device
External differences of analog and digital devices
The credibility of a digital instrument
Reserve error monitoring devices
Safety class multimeter
Metric devices come in two main types: analog and digital. These devices differ in functionality, accuracy of measurement, the assembly quality bundle. In any case, this is a very useful measurement systems for each.
In analog multitester measurement result is displayed by the normal pointer on the scale. Sometimes operation of this analog instrument is not quite appropriate - the beginner or the expert in the field of electrical hard deal with all scales "scale interval" a specific parameter, to calculate the final value of the electrical characteristics.
And yet, an analog tester does not fix the arrow to the position, which makes it difficult to read the result and generally work with the device.
DMM is the measurement results in the form of digital values on the LCD screen. It provides the ultimate ease of operation of the device, eliminates any errors associated with the taking of evidence and calculation of the required parameter, given the "price of division" of the scale. This is one of the main reasons for the popularity of digital multitester masters.
image gallery
Photo of
Control and measuring device configured in stick form, it is more convenient to work
In addition to the usual equipment priborchiki probe, there is a probe-crocodile
For measurement one of the probes extends from the device itself, a second wire is connected
Perform testing using the stylus with clip "Alligator" is much more convenient than the conventional device with two probes. Especially if the measurements necessary to produce the shed
To power the unit uses standard penlight batteries that must be replaced periodically
Significant minus of the device is the inability to measure the strength of the current. Those who need this feature, the device will not work
But the utility voltage multitester Pencil produces without direct contact, it is often necessary to check the flush
Further indications on output characteristics of the display device verification sound indicating the presence of damage
Multitester in stick form
Options multimeter-pencil
Measurement of pencil voltage
Application clamp type "crocodile"
Power supply from the battery
Less device in the form of a pencil
Non-contact detection
The presence of an audio signal
Standard multimeters can cost more than $ 5 But one thing always remains the same - a central place on the panel takes the rotary trigger. It does not change the location of the other controls on the panel corners, the availability of the necessary connectors at the bottom of the panel, colorful symbols.
If you purchase a product, be sure to buy an external silicone covers that protects against dust, moisture, drops from low altitude, has special clips and a stand that can be very useful in unexpected situations operation multitester.
image gallery
Photo of
The easiest to use and inexpensive multitester configured as a screwdriver, to enable a control of AC and DC voltage
When measurements are taken readings are displayed in the measured characteristics of the units
To obtain the voltage in the electric screwdriver tester probe is applied to the conductor free of insulation. When looking for continuity is applied to the insulation
In addition to checking voltage readings at the power supply tester screwdriver helps detect the presence of electromagnetic radiation
The simplest version multitester
Conclusion take readings on display
measurement Features
Electromagnetic radiation
Domestic electrical network
Given the theme of the article and the specifics, we are talking about a metric measuring the household power supply. But to work on the definition of the parameter values, you must have at least a rough idea of the characterization network home electric supply.
A socket in this case serves only as an "exit point" voltage, so it is reasonable that you need to know with any voltage in the outlet will be "working" consumer.
In the world there are several major categories of electrical power networks for household appliances, one of which is "our" 220 V 50 Hz. It is a two wire ( "phase" and "zero"), between which the voltage is 220 V.
In recent years, systems for ensuring private homes and apartments are sometimes connected 3-phase voltage network 380 V with a frequency of 50 Hz, which would be "powered" device such as a pumping station, a compressor, a lathe and etc.
Household electric network "gives" in receptacles voltage 220 V (single phase) for the current household instruments of foreign and domestic production from kettles and hairdryers to dishwashers and washing machines
The question arises: why it is necessary to measure the characteristics of the network? On the one hand the answer is obvious: if you do not know or are not confident in their beliefs relative to the socket, you see in front of you and you need to make any wiring work.
On the other hand, most electrical appliances accurately calculated on a certain frequency and voltage. Some electrical devices designed to work from the mains with a frequency of 60 Hz.
For example, brought a microwave oven made in South Korea is equipped with a transformer, which is from "our" 50 Hz can easily "swell" and she (oven) quickly fail.
Excess or reducing the frequency, voltage and current strength can significantly alter the efficiency of the device, resulting in the electric device comes out of action and subsequent operation impossible. Multimeters are needed for measurement and control of network parameters.
Safety precautions before work
Multitester - is a multifunctional handheld device that is powered by a battery (typically "crown") and is a convenient, safe and most importantly, a tool for the end user. But also for its operation, there are certain rules of use.
"Crown" - the battery of galvanic batteries, dimensions 48,5H26,5H17,5 mm. Mass batteries of about 53-55 grams. Output voltage - 9, capacity on average - 600 mAh
By itself, the tester is equipped with an internal overload protection and overvoltage. But without complying with the rules Below it, too, can easily "burn" partially damaged. To avoid this, there are some general rules for the safe operation of the digital tester.
In measuring the AC input voltage:
- Unless defined preliminary value of the measured voltage, the switch is put in the highest range.
- Not to input voltage greater than 750 V in order to avoid damage to the internal circuit.
Hands without gloves dielectric can not touch the electrical components.
In the measurement of the input AC and DC:
- Unless defined preliminary value of the measured current, the switch is put in the highest range.
- If the LCD display is set to "1", set the trigger to the next range in the direction of increasing the maximum value.
- When working with a connector "20A" test time should not exceed 15 seconds, because in this mode the fuse is missing.
When measuring the internal resistance of the circuit, make sure that the circuit is powered off and all capacitors are discharged under the "zero".
The fuse is a glass tube with external metallic contacts in the form of "caps". Inside the bulb is a piece of wire that is melted at the time of overload, it opens the circuit and keeps the device from damage
Furthermore, there are special rules for maintenance and storage of the device, namely the need not to input voltage if the rotary switch is in Ohm position to operate the device if the housing cover is not completely closed. Finally, the replacement of electrochemical batteries and fuses only when the device is switched off and disconnected probes.
Legend multimeter
Multitester actually consists of several standard units: a display (analog - scale with protective glass) multiposition rotary switch, connectors for probes. In this article, as multimetricheskogo device is considered DT9205A model.
Multitester digital DT9205A has ample opportunity, including the measurement of AC and DC voltage and current, resistance, capacitance, diode serviceability. Size - 186h86h41 mm; weight - 318 grams
buttons:
- ON / OFF - switch on / off the device;
- HOLD - Hold displayed value on the LCD screen.
Sector central switch:
- hFE - measuring parameters of transistors;
- F, Ω- testing capacitors and resistance;
- A-, A ~ - DC and AC current;
- V-, V ~ - DC and AC voltage.
Main Connectors:
- 20A - inlet for measuring current to 20A, the red probe;
- A - socket for testing amperage within the ranges;
- COM - jack of all modes, typically connects the black lead;
- VΩ - jack for measuring voltages and resistances.
Connectors sections "pnp / npn" - testing semiconductors, "cx" - connectors for inserting the inspected capacitor. Be sure to observe polarity or he "bulges".
In order to correctly use multitester should know what functions he is endowed with. Buttons designation functions are located on the front panel (+)
Connecting the probe to the multimeter
Probes - a special kind of connectors, that help measure the characteristics of the electrical components and parts of a wired circuit. They can easily connect the necessary connectors multitester with other outputs.
It is usually a metal rod and the plastic insulation, one end of which rod with the other output - with the connector wire to be inserted into connectors 20A, A, COM and VΩ device.
Additionally, sometimes in an arsenal is necessary to have an additional set of probes, but instead uses metal rod "crocodile" - crocodile clips.
"Crocodile" is a special kind of nozzles for probes multitester, very convenient when measuring the electrical characteristics of the medium and large details
Most of the instruments are imported from China, where they are manufactured in factories, shops and mini-workshops. In this regard, manufacturers save on everything, including materials for the probe, which are easily damaged.
Recommended probes do it yourself by buying parts at the radio market or Radio Shack. Instead of insulating plastic is often used ampulki and empty shell for ballpoint pens.
COM connector is an electrical "net", performs the function of the ground in all modes and bands. Usually here connect the black lead
Connect the black test lead plug into the socket with multimeter symbol COM. A red lead into the connector plug connect with the designation VΩ, which is for measurement of direct and alternating voltage.
We strongly recommend not to clamp the red and black test lead to the contact in any mode, the exception - circular switch in position "►" (proring chain).
Furthermore multitester voltage can be measured current value and the resistance value. It is important to remember to turn off the power when measuring the resistance value
Measuring AC voltage in the socket
Study and preparatory work produced. We turn to the actual performance of the task. The first thing multitester disable, if it is enabled. Push the ON / OFF button.
Translate rotary trigger multimeter to "750" (in other testers may be 600, 1000) section "V ~". This means that the device can measure the parameters of AC voltage in the range from 0 to 750 V.
If you put the desired range is less than the nominal voltage (less than 200), it can damage the appliance, thus creating a situation of over-voltage. In the best case, it will have to change the fuse, and at worst - "empty" multitester for parts
Turn on the tester, on the LCD screen should appear at least one "zero" - the device is ready for use. Set up probes in socket holes in turn, does not matter how much. Take readings AC household power supply.
Values on the screen jump and do not show exactly 220 - this is normal, because we are dealing with a single-phase network with variable voltage
The power supply testing work should be carried out carefully enough, slowly and do not touch any exposed parts of the leads.
Current measurement in the socket
Never and under no circumstances do not measure AC power outlet multitester directly, without the connected load. If you just stick two probes from the tester into the outlet, you can "say goodbye" to the device. The result is a "New Year's fireworks," and burned The electric device.
current in normal outlet successively measured is required to the connected load "tester-socket" circuit. In even an ordinary light bulb with a cartridge (place screwing the lamp) can act as a unit load.
For the correct measuring current in the circuit, switch the trigger on the maximum position of the section "A ~", in the present value of the instrument is 20 amperes. Red swap probe into the socket with the "20A" inscription (UNFUSED - mode without a fuse, FUSED - fuse mode)
Sequentially connecting the tester and a light bulb, one of the probes inserted into the socket, to another probe connect one wire of the cap lamp. The second wire bulb inserted into the socket hole free. Remove the amperage. It is not recommended to measure more than 15 seconds of time.
Yet, the current strength is not recommended to be measured in the outlet. It does not carry any meaning. Domestic electrical network It has a maximum limit in amperes, which must be observed. The current strength always exists only in the presence of a load, where we measure the current.
Measuring the voltage and current of the battery
current measurement in return in the socket, it is better to learn how to measure DC current and voltage of the batteries, accumulators and power supplies. It is much more interesting and safer. In addition, these electric elements each sufficiently. They usually have things such as cameras, phones, tablets, toys, etc.
Batteries and accumulators can be easily distinguished: they all have a special inscription near the output contacts as icons "+" and "-". Test these elements are not just no more difficult than a voltage or current in the socket.
image gallery
Photo of
To measure the voltage indicators plus the probe is connected to the right jack
Negative probe of the testing device is connected to the central socket on the front panel
To measure the DC power supply voltage selector is set to the corresponding segment. In addition, measurement limit is set, for example, the battery 2 is v
To measure the voltage in the power supply, the working limit of which is 18 v, the switch should be set to a position 20 indicates the v
If during the measurement apparatus exhibits minus figures mean confused plus-minus, therefore, probes must be applied on the other side
In order to measure the alternating voltage, the switch is transferred to the corresponding segment is situated to the right of the device
In order not to burn the tester when removing the AC voltage readings, it is better to set the top limit of the measurement
Measurements are performed by immersing the probes in the contact holes outlet, during normal operation, the network device will show 220 - 230 v
Connecting the positive multimeter probe
Connecting device minus probe
Installing DC voltage limit
Setting the measurement range for the power supply
EXAMPLE incorrect probe locations before testing
Switch to AC voltage test
Subtleties testing AC voltage
Standard AC voltage readings
It should be noted that these power elements are usually characterized by small values of voltage and current. To measure the DC voltage or current on the battery is necessary to switch the rotary trigger multitester in sections corresponding mode "V-" or "A-" of which is greater than the value specified in the outer shell element.
Turn on the tester. Black test lead (zero) is connected to "-", and the red probe is aligned with the "+". Remove the fixed constant value. This way you can measure the main electrical parameters of the battery, which will help determine their operating status.
Conclusions and useful videos on the topic
Movie will demonstrate the sequence of actions during the measurement dynamics:
Article available is about how to measure the voltage and current in the socket and all his friends are unfamiliar with and elektrotochkami electrical wiring. Using a multimeter will significantly reduce the risk of dangerous situations in the device and wiring repair, replacement of sockets and switches.
Want to report information about the use of the meter? There were questions in the process of familiarization with the article? Please write comments in the unit for the feedback.
