In the market there are two types ohmmeter, namely ohmmeter ohmmeter series and parallel. In general, this series ohmmeter circuit consists of a meter basis in the form miliammeter / mikroammeter direct current, some resistors and potentiometers as well as a direct voltage source / battery. V is a direct voltage source / battery and RM is the resistance in the basic meter M.
Figure 8.4 Basic circuit Ohmmeter Series
At first taken RX = zero or AB linked so obtained flows through the meter M is:
In such circumstances R2 is set to meter M indicates the maximum price. Imaks = full-scale current (full-scale). When taken RX = infinity or AB in an open state, it is obtained:
IM = 0
Now suppose a resistor RX mounted on AB, then the current through M are:
thus:
In the equation IM = the current flowing through the meter M and RX = resistance measured.