# Parts and Functions of Multitester or Voltage Ohm Meter

The VOM or Voltage Ohm meter or commonly called as Multitester is used by the technicians or enthusiasts both Electronic or computer technician. This equipment is used to measure both the voltage AC and DC voltages, Resistance, and current. Remember that you will deal with the high voltage in using this equipment. So therefore you need to learn more about how to use this and learn first the parts and functions including the safety precautions.

1. Know what to be measure- remember that before you perform measurement of a voltage or a device you should acquaint yourself what type of current your dealing with. Is this high voltage or not, example: the wall outlet electricity or the convenience outlet or CO that has a standard wall outlet electricity of 220 VAC minimum.
2. Know the polarity- if we should measure a line of voltages or current we must understand that a Direct Current (DC) have a two channel, the positive and negative. To avoid an incident, we must always avoid the technician error in considering the trial and errors.
3. Do not hold the test rod- the test rod is the metal tip of the test probe, consider always the voltage and electronic component as high voltage. So that you will avoid the accident of electrical shock and damage of the units you repair.

### THE BASIC PARTS OF THE VOM (Multitester)

Remember that there are different type of the analog multitester through the manufacturer, the unit I’ve use is the Sanwa YX360 TRF and the Sunwa YX360 TRD.
1. The Dial or the Infinity knob- this is the zero collector whenever you calibrate, the beginning as 0 voltages both the AC and DC measurement. Use your flat screw driver to set this knob to calibrate the 0 voltages of your tester. The name alone as Infinity knob because 0 voltage region of the tester is the infinity region of the resistance. Because the principle of the Multitester is “The higher the measurement of the voltage, the lower the resistance."
2. Zero Adjustment or the Zero Ohms collector knob- this use to calibrate the tester whenever you wanted to measure the resistance. To assure that the tester calibrated to zero Ohms, just follow this procedure. Take the two metal tip of the test probe of the VOM connected
Then look at the meter scale of the tester, notice the needle or the pointer if it takes to the zero ohms situated right of the meter scale. If the needle didn't take to the zero ohms just rolled the knob clockwise until the middle position in the zero ohms.
3. The pointer or needle- use to point or read the measurement using the meter scale base of the range and settings you prepared during the test of a device or line of a voltage.
4. Meter scales- this is the basis of the measurement where the graduation, bar drawn in the body, commonly the resistance or ohms scale have a measurement from 0-2k ohms depend of the range and settings. And the voltage both AC and DC from 0-250,50, 10 and it depends on the range and settings you sited.
5. Range selector knob- this part of the tester located center down of the body of the VOM is used to select the range and settings of the VOM the (AC and DC, Resistance, and the Amperage). Be sure to set this if ever you wanted to measure the voltage. If you forgot to sit this part, and the settings are the resistance, then you measure the voltage, this will cause blown off your VOM and may possibly cause damage of your VOM.
6. Range and settings- position in the whole corner of the range selector knows. Written here the voltages AC and DC, Resistance or ohms, and the amperage ranges. So if you wanted to measure be sure to know what you wanted to measure so that you can sit your settings, example Voltage AC 220 Volts.
7. Test probes- there are two test probes of the VOM, the black is the negative (-) and the red is the positive (-). If ever you wanted to measure a voltage, example DC just knows the polarity or the positive and negative. Then connect the test probe red to the positive line of the circuit and the black probe to the negative or the ground (GND) of the circuit or of the dry cells.

TIPS!

• If you want a good performance and to assure an exact result use a non-pirated or original VOM.
• Buying original VOM, you can assure of your safety, because electricity is very dangerous to us and may can kill.
• Be sure to calibrate first the VOM before to test any voltages higher or not.
• Always off VOM after use to assure the life span of the VOM battery.