NGPS – User’s Manual
29
A typical example of a regulation fault is represented by a 1Ω load connected
to a NGPS 200-50 (i.e. the maximum power supply output voltage is 50V, see
: Standard NGPS models). By setting a current of 100A to the load, the output voltage
would reach a value of 100V, which obviously is not feasible with this model. Indeed,
once the power unit supplies 50A to the load, it has already reached the maximum
output voltage condition. The power unit recognizes the difference between the set-
point (100A) and the actual output current (50 A), thus generating a “regulation fault”
condition.
The tripping of this fault implies an automatic turning off of the NGPS unit. A
status reset – i.e. reset faults – needs to be performed in order to turn the unit back on.
OVerPower - OVP
The NGPS can work continuously at 1% over its power rating (see
The module is able to work at a power comprised between 1% and 5% over its
rating – i.e. between 101% and 105% – for a 20-seconds interval before turning off and
tripping an over-power fault.
If the requested output power is more than 5% above the nominal ratings, the
power unit will suddenly shut down after 1 second.
This behaviour is summarized in
(a realistic example of a NGPS 200-
50 unit is also listed), where
P
N
is the rated nominal output power of the power supply
unit, as indicated in
Output Power
Time of Operation
< 101% of P
N
e.g. NGPS 200-50: < 10.1 kW
Continuous
> 101% and < 105% of P
N
e.g. NGPS 200-50: > 10.1 kW and < 10.5 kW
20 s
≥ 105% of P
N
e.g. NGPS 200-50: ≥ 10.5 kW
1 s
Table 7:
Time of operation of an NGPS under over power condition
OVerTemperature - OVT
Internal monitoring of temperature is performed in different places inside the
NGPS power supply. If a pre-defined threshold is exceeded by any of these internal
sensors, an OVT condition is generated, thus shutting off the power unit.
