Power meter requirements so to measure mobile phone charger Stand-by power

[Kiriakos GR]

Power meter requirements so to measure mobile phone charger Stand-by power .

Intro:
Most cell phone chargers are switching power supplies.
First, 220V is rectified into DC power, and then through high-frequency conversion, coupled through a pulse transformer, unidirectional rectification outputs low-voltage DC.

Even though there is no output current, the high frequency conversion part is still working and needs to consume some power.
For example, the control circuit in the charger mainly detects whether the phone is connected to the charger.
The control circuit will also function when the charger is not connected to the phone.

Another example is a load element (an indicator of a single charger) that also works when plugged in and also draws a portion of the power.
Simply put, devices like chargers are bound to draw power when plugged in.


The People's Republic of China Communication Industry Standard yd-t1591-2009 "Technical Requirements and Test Methods for Power Adapters and Charging/Data Interfaces for Mobile Communication Terminals" stipulates that the rated output current of the power adapter should be in the range of 500mA to 1500 mA, determined by the manufacturer.

The AC line power consumption is less than 150 mW without the load as power consumption of the power adapter.
The regular chargers we use will comply with the relevant national standards.

The required high precision digital power meter it should incorporates a new design architecture with many optimizations for low power measurements.
It minimum measuring AC current ability should be as low as 50μA (micro Ampere), and to can measure power consumption as low as 0.01W.

Such equipment it does meets the tests of international standards (IEC62301, Energy Star, Low power measuring specification).