DER-43

24.5 W Telecom Line Card PSU

November 18, 2004

15 Other Test Results

During short circuit, the following happened:

-

for –28 V short circuit, the power supply went into autorestart

-

for –65 V short circuit, the power supply shut-down. The power supply would

normally go into autorestart under this condition. However, since the –40 VDC

input rail is used to derive the output of –65 VDC, when the –65 VDC output is

shorted, this also shorts the input voltage and causes the power supply to go into

under-voltage shutdown (which occurs when the input voltage drops below ~ 32

VDC).

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