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There are simple, and more complex (and more accurate) circuits for this. One nice pair I've seen was at HomePower.com magazine, in their very early issues. To check the state-of-charge of a deep-cycle battery on your solar power setup, for example, you want to see voltages between maybe ten and twenty volts. The range down to zero is of less interest, and the resolution of reading the meter is better if you skip those. Mark the meter accordingly (even tape tabs on the glass.)
The simple one uses a Zener diode at maybe ten volts, and a dropping resistor to give the diode enough current to be stable, and if possible, maybe ten times the current that the (D'Arsonval moving-coil) meter movement uses, Then the meter and its series resistor reads the remaining voltage across that dropping resistor, from say ten to twenty volts offset. As long as the meter is carrying a small percentage of the total current, accuracy isn't too bad. If Zener current is ten mA (and times ten volts, the diode dissipates 100mW), then a one mA meter won't load it too much. Inexpensive meters are widely available down to 50microAmps, just set it up so ten volts puts the full-scale current through it, with a fixed resistor and potentiometer totalling a little less than (10v/.00005A)=200kOhms. Maybe 180kOhm and a 25k pot for the finer adjustment, set to read full scale at ten volts. Part of the pot's range makes up for the internal resistance of the meter, which can be measured, but isn't really needed to work well.
The (slightly) more complicated circuit uses the venerable old 723 voltage regulator, set up for the same ten-volt offset, and adjustable for exact offset with the same meter idea. Circuits for both should be at www.homepower.com archives.
If you only need to check occasionally (and not dissipate full-time too much of your hard-won solar Amperes), just connect the meter with a push-to-measure button.
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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 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.
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 are the precaution before using a multimeter dc voltmeter and dc ammeter?
Make sure the the Leeds are inserted in the right hole. Make sure that the meter is set to the range of voltage or current you expect
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 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.
