KEPCO HSM Series - Manual (Page 33)

HSMSERIES OPR 052912
3-9
3.14.2 OUTPUT STATUS FLAGS
The OUTPUT STATUS flags are controlled by the output fault detector circuit, which monitors
both output voltage and module current to assess d-c output status. An output fault condition is
generated if one of three fault conditions is detected: (1) Overvoltage fault, (2) Undervoltage
Fault - output voltage is outside specified regulation limits, or (3) Undercurrent fault - the power
supply module is supplying less than 70% of the current required by the circuit (as indicated by
the load sharing signal) while the output voltage is within specification limits.
A fault condition is not generated for a combination of overvoltage and undercurrent indications,
as these are mutually exclusive conditions for power supplies which are not part of a parallel-
redundantconfiguration; this combination does, however, indicate proper operation for opera-
tional power supply modules which are part of a parallel-redundant power scheme in which one
or more power supply modules are presenting overvoltage failures.
FIGURE 3-6. TIMING DIAGRAM FOR POWER AND DCFAIL STATUS