Lian Li EG1200G ATX v3.1 power supply review – L-shaped drawer design for more elegant cabling

1 - Introduction, overview and technical data 2 - Unboxing, cables and protective circuits 3 - Teardown: Topology, components, processing 4 - Load Regulation, Ripple Suppression 5 - Transient Response 6 - Hold-Up Time, Timings, Inrush-Current 7 - Average Efficiency and PF 8 - Operating noise and fans 9 - Summary and conclusion

Hold-up time (bridging time)

Hold-up time is a bridging time that describes the period during which the specified output power continues to be provided in the event of an input voltage failure. Even normal power supply units can bridge short-term power failures of up to a few seconds using appropriately dimensioned input storage electrolytic capacitors. The hold-up time is short compared to other power supply units with similar performance, but exceeds 17 ms. The hold-up time of the power OK signal is less than 16 ms, but meets the requirements of the ATX v3.1 specification. Note: The latest ATX specification is less strict in this area than the older versions.

01 hold_up_time-2

02 ac_loss_hold_up_time-2

03 pwr_ok_inactive_to_dc_loss_delay-2

Inrush current (starting current or inrush current)

All power supply units generate a so-called inrush current, which often far exceeds their nominal current consumption. The causes are the charging of the different capacitances in the input circuit and in the EMC filters, the build-up of the magnetic field in the transformer core and even the charging of the capacitors in the output filter. This input current only drops back to normal values when the converter is operating stably. The inrush currents are well controlled at both input voltages.

01 inrush_current_230V-2

02 inrush_current_115V-2

Timings

The power supply supports alternative low-power modes.

01 timing_20_t1-2

02 timing_20_t3-2

03 timing_100_t1-2

04 timing_100_t3-2