What would you like to do?
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 ar…e 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.
Multi-range ammeter using universal shunt
Cross the beams.
If you are talking about house wire, touch the ends of the black and white wires. The black and ground wires will work the same.
If you use a series resistance equal to the voltmeter resistance, then an external voltage is split equally between the voltmeter and the resistance since the same current flo…ws through both (even though in a good voltmeter that current is very small). So you can apply twice the voltage to get full scale deflection. In the end, it is current which causes the meter to register. So for a meter resistance R and a series resistance r, the voltage range of the meter is multiplied by the ratio (R+r)/R.
It could be when the positive wire is plugged in the negative slot and the negative wire is plugged in the positive slot. This can make the readings negative.
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.
Through the use of a 'multiplier', i.e. a carefully-calibrated resistor connected in series with (in the case of an analogue instrument) the instrument's operating coil.
What is your question.
If you place an OHM meter across a resistor, it will read resistance. An OHM meter set to read voltage will read any voltage present. So, if you pick up a resistor, connec…t it to a volt meter, in theory, no voltage will be present. Unless you're feeding some sort of electricity through it. I'm certainly not an electrical engineer, I do however use a volt/ohm meter occasionally. A volt/ohm meter is a dual/multi purpose piece of equipment.
It is the maximum voltage to which it has been calibrated, but this may be set out in separate ranges selected by a switch on the front panel.
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-ran…ge voltmeter is 125 volts.
To read the voltmeter, make use of the test leads.
For higher voltage ranges, the series resistance may be connected externally and this is the main reason.
A voltmeter tells volts. A volt is a joule per coulomb or a normed coulomb per metre.