An ammeter has a very low internal resistance. So, if it is connected in parallel with a load, it will short-out that load in resulting a high current flowing through the ammeter may severely damage the ammeter (and possible harm the user), although most are fitted with fuses to protect them.
Should an ammeter be connected in parallel?
The circuit must be broken to correctly insert an ammeter. Ammeters have very low resistance to minimize the potential drop through the ammeter and the ammeters impact on the circuit, so inserting an ammeter into a circuit in parallel can result in extremely high currents and may destroy the ammeter.
Why ammeter has low resistance and voltmeter has high resistance?
ammeter has low resistance because it is a instrument which measures the electric current in amperes in a branch of a circuit . It must be placed in series with the measured branch , and must have very low resistance to avoid significant alternation of the current it is to measure . So, it should have high resistance .
What are the dangers and consequences of connecting an ammeter in parallel?
The low resistance ammeter makes the effective resistance of the circuit very low and so the current is very big. The ammeter actually shorts out the component its trying to measure the current through. This can damage the ammeter because a very big current flows in it.
Just like voltmeters, ammeters tend to influence the amount of current in the circuits theyre connected to. However, unlike the ideal voltmeter, the ideal ammeter has zero internal resistance, so as to drop as little voltage as possible as current flows through it.