Engineering Prototype Report

EPR-00010

Page 21 of 24

8.8 Surge Voltage

8.8.1 Differential = line-to-line (L-N), 2 ohm source impedance.

The unit exceeded the 1kV IEC/UL 1000-4-5 Class 3 requirement (meets Class 4, 2kV).

The CX1 capacitor failed after more than 20 2.5kV surges.

During the 2.5kV surge, the unit turns off for approximately 1.8 seconds.

Figure 8.8.1 C1 (DC bus) voltage after the 2.5kV surge.

8.8.2 Common mode = line-to-ground (L-GND, N-GND), 12 ohm source impedance

The unit exceeded the IEC/UL 1000-4-5 Class 3, 2kV and Class 4, 4kV requirements.

The maximum test voltage was 6kV. During the 6kV surges, the unit continues to operate.

The unit was centered on the insulation side of a 6 in x 4 in single sided copper clad

board (1/16 in insulation), to avoid surface or insulation breakdown during the voltage

surges. The voltage was applied between the input terminals of the unit (L or N) and the

copper clad ground plane (GND), in the following sequence:

L(+6kV) to GND , 5 times

L(-6kV) to GND , 5 times

N(+6kV) to GND , 5 times

N(-6kV) to GND , 5 times

DC voltage level at

230Vac, 60 Hz.

ON

OFF

ON

100V/div, 500msec/div

Power Supply State