you need
  • tester table resistivity.
Guide
1
To reduce power current on the circuit and change the values ​​on which it depends.To determine these values, use the equation, which is a type of write Ohm's law I = U • S / (ρ • l).Assemble the chain by connecting to the test site a rheostat.Connect it to a power current .After that, changing the setting of the rheostat, reduce tension in the area.In order to obtain figures voltage, connect in parallel to the tester and make a measurement.Then, by connecting the tester to the site and changing consistently, measure force current in the circuit.Lower voltage on the circuit by n times.By measuring the force current , make sure that it also decreased n times.
2
Change the resistance of the circuit.To do this, determine the resistivity of the conductor material at a special table.To reduce the strength of the current pick conductors of the same size, but with a high resistivity.How many times will increase the resistivity, so many times will decrease the strength of the current .
3
If you can not pick up the other conductors change their geometric dimensions.Reduce the cross-sectional area of ​​the conductor.For example, if stranded wire, remove a few strands.How many times will decrease the cross sectional area, the same factor decreases current.The second way - to increase the overall length of the conductors.How many times will increase the length of the conductors on the circuit, so many times will decrease the strength of the current .
4
Another easy way - attach the chain to the source current less electromotive force.How many times will decrease the value of the EMF, so many times will decrease the strength of the current .These techniques can be combined to achieve the desired effect.For example, lowering the voltage 2 times, increasing the length of the conductors 3 times and reduce the cross-sectional area 4 times, you will get a reduction of force current 2 • 3 • 4 = 24 times.