Sices HS 315, Техническое руководство

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126 Technical Handbook
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P.0226: threshold (percentage of P.0102) under which the engine is considered
stopped.
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P.0227: threshold (percentage of P.0102) over which the engine is considered started.
•
P.0301: low generator voltage threshold (percentage of P.0102); under this value the
generator cannot be connected to the loads.
•
P.0303: high generator voltage threshold (percentage of P.0102); over this value the
generator cannot be connected to the loads.
Here follows an example about the various threshold used, including default values for a.m.
parameters.
Parameter Description Default value Voltage in Volts
P.0102 Nominal voltage (AC) of the
generator. 400 V 400
P.0226 Threshold for engine stopped
(Vac). 17.5 % 70
P.0227 Threshold for engine started
(Vac). 20.0 % 80
P.0301 Minimum voltage threshold. 75.0 % 300
P.0303 Maximum voltage threshold. 112.5 % 450
P.0202 Hysteresis for generator's
measures.
2.5 % 10
The hysteresis fully configured in the direction for the threshold entry, applies to the two
configurable thresholds (P.0301 e P.0303). This means that generator voltage is out of the
tolerance if out of the thresholds P.0301 and P.0303; it is in tolerance if between P.0301 +
hysteresis and P.0303
– hysteresis; otherwise, the previous status is maintained.
Keeping in account these values, the following bands are defined:
0 V .
A band: Absent
70 V .
B band: Hysteresis
80 V .
C band: Low
300 V .
D band: Hysteresis
310 (300+10) V .
E band: In tolerance
440 (450-10) V .
F band: Hysteresis
450 V .
G band: High
xxx V .
If the voltage is in
the “B”, “D” or “F” bands, previous status is maintained (hysteresis). For
example, if the voltage was in the “E” band and now it is in “D” band, it is considered however
“In tolerance”. On the contrary, if voltage was in the “C” band and now is in “D” band, it is
considered
“Low”.
In single-phase systems, these tests are executed on phase-to-neutral voltage.
In three-phases systems, these tests are executed on all phase-to-phase voltages. If the
neutral is connected to the terminal JG-4 (P.9614 =
“028”), these tests are executed on the
three phase-to-neutral voltages too.
Thresholds P.0301 and P.0303 are used also to manage the generator protections on voltage.
These protections can be individually disabled setting to zero the relevant parameter that
specifies the delay (respectively P.0302 and P.0304). Thresholds are however used to define