1A Source and 500mA Load (Q001E)

 

 

I have a 1 A (1000 mA) power supply and I want to power a lamp which consumes only 500 mA. If I connect this source to the lamp won’t it burn?

 

This is a very common question among our readers. Powering a load with a source that requires more current than this load requires. What happens is simple If the load is 12 V and the source 12 V, for example, the load will "pull" from the source only the current it needs. A 12 V x 500mA lamp connected to any source that provides more than 500 mA will only drain 500 mA, no matter what the supply current is, so it does not burn. In fact, it is common to always use a source with a capacity slightly higher than the load required, so that it works with some flexibility. But beware: there are certain sources that only provide the voltage when the current is marked. With smaller currents, these sources can have higher voltages and this mainly occurs with many low cost batteries eliminators.

 

 


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