Ammeters measure amperage, or current flow, in a circuit, and provide information on current draw as well as circuit continuity. High current flow indicates a short circuit, unintentional ground or a defective component. Some type of defect has lowered the circuit resistance. Low current flow may indicate high resistance or a poor connection in the circuit or a discharged battery. No current indicates an open circuit or loss of power.
Ammeters must always be connected in series with the circuit, never in parallel. That is, all the circuit current must flow through the meter. It is connected by attaching the positive lead to the positive or battery side of the circuit, and the negative lead to negative or ground side of the circuit, as shown. CAUTION: These meters have extremely low internal resistance. If connected in parallel, the current running through the parallel branch created by the meter might be high enough to damage the meter along with the circuit the meter is connected to. Also, since all the current will How through the ammeter when it is connected be sure that the circuit current will not exceed the maximum rating of the meter.
There is not a great difference between analog and digital ammeters. Digital meters are often capable of measuring smaller currents, all the way down to microamps. They are easier to use because they give a specific value, eliminating the need to interpret the analog meter's needle on its scale. Generally speaking, most digital ammeters are combined with a voltmeter.
Was this article helpful?
You can now recondition your old batteries at home and bring them back to 100 percent of their working condition. This guide will enable you to revive All NiCd batteries regardless of brand and battery volt. It will give you the required information on how to re-energize and revive your NiCd batteries through the RVD process, charging method and charging guidelines.