Parts of multi tester

Answer 1

Multimeters vary depending on manufacturer and price.

The most common elements are.

Voltage Ac and DC

Current in Amps

and Resistance in Ohms.

For voltage, select the maximum range you are likely to see.

Put the red lead on positive and black lead on negative part of the circuit or power supply you are testing.

For current, Disconnect one lead of the power supply. Select the Current range you are likely to see (sometimes involves changing one of the test probe sockets) Put one lead on the supply and the other on the wire you have disconnected, so the meter is in series with the supply.

For resistance, you can check the absolute value of a resistor, or check for continuity or insulation of a conductor. Put the leads at either end of the device or circuit you are testing. 0 Ohms = little or no resistance, cable conducts.

No reading = open circuit, or insulation OK.

Select minimum range for conductivity and max range to check insulation.

Answer 2

The parts of a multi tester are:

• indicator zero corrector
• range selector switch knob
• measuring terminal +
• measuring terminal - COM (common)
• Output
• Adjusting knob
• Panel
• Indicator panel
• rear case bolt
• rear case
• Connector for the test
• Connection pi to tester
• Transistor base clip
• transistor collector clip

A multi tester is an electronic measuring instrument that measures things like voltage, current, and resistance.

Answer 3

Ø The dial. This has the arc shaped scales visible through the window. The pointer indicates values read from the scale.

Ø The pointer or needle, this is the thin black line at the left-most position in the dial face window in the image. The needle moves to the value measured.

Ø Arc shaped lines or scales on the meter dial face. May be different colors for each scale but will have different values. These determine the ranges of magnitude.

Ø A wider mirror like surface shaped like the scales mentioned previously might also be present. The mirror is used to help reduce parallax viewing error by lining up the pointer with its reflection before reading the value the pointer is indicating. In the image, it appears as a wide gray strip between the red and black scales.

Ø A selector switch or knob. This allows changing the function (volts, ohms, amps) and scale (x1, x10, etc.) of the meter. Many functions have multiple ranges. It is important to have both set correctly, otherwise serious damage to the meter or harm to the operator may result. Most meters employ the knob type like the one shown in the image, but there are others. Regardless of the type, they work similarly. Some meters (like the one in the image above) have an "Off" position on this selector switch while others have a separate switch to turn the meter off. The meter should be set to off when stored.

Ø Jacks or openings in the case to insert test leads. Most multimeters have several jacks. The one pictured has just two. One is usually labeled "COM" or (-) for common and negative. This is where the black test lead is connected. It will be used for nearly every measurement taken. The other jack(s) is labeled "V (+) and the Omega symbol" (an upside down horseshoe) for Volts and Ohms respectively and positive. The + and - symbols represent the polarity of probes when set for and testing DC volts. If the test leads were installed as suggested, the red lead would be positive as compared to the black test lead. This is nice to know when the circuit under test isn't labeled + or -, as is usually the case. Many meters have additional jacks that are required for current or high voltage tests. It is equally important to have the test leads connected to the proper jacks as it is to have the selector switch range and test type (volts, amps, ohms) set. All must be correct. Consult the meter manual if unsure which jacks should be used.

Ø Test leads. There should be (2) test leads or probes. Generally, one is black and the other red.

Ø Battery and fuse compartment. Usually found on the reverse, but sometimes on the side. This holds the fuse (and possibly a spare) and the battery that supplies power to the meter for resistance tests. The meter may have more than one battery and they may be of different sizes. A fuse is provided to help protect the meter movement. Sometimes there is more than one fuse. A good fuse is required for the meter to function. Fully charged batteries will be required for resistance / continuity tests.

Ø Zero Adjustment. This is a small knob usually located near the dial that is labeled "Ohms Adjust", "0 Adj", or similar. This is used only in the ohms or resistance range while the probes are shorted together (touching each other). Rotate the knob slowly to move the needle as close to the 0 position on the Ohms scale as possible. If new batteries are installed, this should be easy to do - a needle that will not go to zero indicates weak batteries that should be replaced.

Answer 4

A multi tester is three test instruments in one. It has the ability to measure the voltage produced by a power source. Secondly it can be used to check the resistance of components, this scale can also be used for checking continuity of a circuit. Lastly it has the ability to check small current flows usually in DC circuits.