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The easiest way is to put a high resistance in series with the meter.
You must know the input resistance of the meter. This is specified in the owner manual.
Some meters are specified as having a certain input resistance.
If a meter has a 1 Megohm input resistance, you can scale it up by a factor of ten by putting a 9 Megohm resistor in series with one of the probes.
Some meters are specified in "ohms per volt".
The Ohms/V rating can be different on different scales. If a meter is specified on the 600 volt scale as having "20,000 Ohms per Volt", then this means that the meter's resistance is 20,000 * 600, = 12,000,000 Ohms. 12 Megohms.
To expand the meter's 600V scale to 10X the rating (6,000 volts), you would put a 108 megohm resistance in series with the probe. This resistance could be made up of ten 10 Megohm resistors, a 7.5 megohm resistor, and a 470 Ohm resistor. Even though that is only 107.97 megohms, the error is less than 1%.
To expand the scale to 2X (1,200V) you would put a 12 megohm resistance in series with the probe.
High voltage low power resistor strings can be put inside plastic, glass, or ceramic pipes. Consult the appropriate industry publications for recommendations.
warning:
Be careful when measuring high voltages. Never work alone.
Most simple resistors are not rated for high voltage over 200-500 volts per each resistor and will arc or burn. Injury or death may result.
I prefer to hook the "hot" end of the probe to the high voltage test point and let it hang there, and not to hold it by hand. Then I energize the equipment and take the readings. After I am done, I discharge the high voltage and safely remove the probe from the equipment.
Poorly made or defective probes have killed people.
Wiki User
∙ 15y ago
Wiki User
∙ 9y agoFor higher voltage ranges, the series resistance may be connected externally and this is the main reason.
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What are the effects on the voltmeter if voltages measured exceed the range?
If the voltage measured exceeds the voltmeter range then the voltmeter needle remains in it's maximum position until it's voltage values are considerably reduced.
What does a voltmeter measure voltage in?
A voltmeter measures voltage in volts.
Convortion of moving coil galvanometrr into voltmeter?
A galvanometer can be converted into a voltmeter by connecting it with very high resistance.
What is an ac voltmeter?
A: It is a regular DC voltmeter but the AC is rectified and the DC component is measured and displayed as AC VOLTS.
Why is ideal resistance of a voltmeter infinity?
generally voltmeters are connected in parallel in the circuit.If the voltmeter resistance is lower as it increases the current rating,because by connecting parallel we are decreasing the resistance,so if the voltmeter resistance is not too much higher it leads to burning of the meter,For that we can conclude that the in ideal the voltmeter has infinite resistance.
Why there is an extension range of voltmeter when a series resistance not equal to voltmeter is used?
why is extention
What are the effects on the voltmeter if voltages measured exceed the range?
If the voltage measured exceeds the voltmeter range then the voltmeter needle remains in it's maximum position until it's voltage values are considerably reduced.
A multirange voltmeter which scale is numbered from 0 through to 250 the pointer falls mid range on the scale interpret the reading on the meter?
With the pointer mid range on the scale, the reading of the multi-range voltmeter would be 125 volts.With the pointer mid range on the scale, the reading of the multi-range voltmeter is 125 volts.
How would you extend the range of a voltmeter and ammeter?
if we would like to expand the range of voltmeter we should change the voltmeter resistance even to be appropriate . we should use a variable resistance to control of its value . I would extend the range of a voltmeter by adding resistance in series with it. I would extend the range of an ammeter by connecting resistance in paerallel with it.
What are two familiar mistakes when using an ohmmeter and a voltmeter?
Voltmeter connect in parallel with the circuit setting on voltmeter highest range first then to lower range. Ohmmeter we need to use the ohmmeter meter setting connect across the resistor
What is range of 0-2Volt voltmeter?
2 volts
What is a multi range voltmeter?
Multi-range ammeter using universal shunt
What range should the voltmeter be set prior to taking a voltage measurement?
If the voltage is completely unknown, a voltmeter should be set to the maximum range first, then stepped down to an accurate level.
What range should you set the voltmeter prior to taking a voltage measurement?
Make a guess of what the voltage will be and set the range accordingly. If needed, change the range after measuring the voltage, to get a better reading.
A DC voltmeter has a resistance of 20000 ohms per volt What is the resistance of the meter if the range selection switch is set on the 250 volt range?
5 megohms
What happen to the range of energies of the particles in matter when the temperature is increased?
the range of energies becomes broader, or increases, as the temperature is increased.
What happens inside a voltmeter when you switch it from a lower to a higher voltage range?
When you switch a voltmeter from a lower to a higher voltage range, an additional resistor is added in series with the meter, increasing the voltage necessary to create the same voltage drop across or current flow through the actual meter movement.
