likströmväxel

A likströmväxel, often translated as a direct current shunt, is an electrical component used in direct current (DC) circuits. It is essentially a resistor with a very low resistance value. The primary purpose of a likströmväxel is to divert a portion of the main direct current away from a sensitive measuring instrument, such as an ammeter.

When a likströmväxel is connected in parallel with an ammeter, it creates an alternative path for the current to flow. Since the likströmväxel has a significantly lower resistance than the ammeter, most of the current will pass through the likströmväxel, while only a small, controlled fraction will flow through the ammeter. This allows the ammeter, which typically has a limited current capacity, to measure large currents without being overloaded and damaged.

The value of the resistance in a likströmväxel is precisely calculated to ensure that the current passing through the ammeter is within its measurable range. This ratio of resistances between the likströmväxel and the ammeter determines the overall current range that can be measured. By using different likströmväxlar with varying resistance values, a single ammeter can be adapted to measure a wide spectrum of currents. This technique is crucial for accurate current measurement in various DC applications.