Alstom MiCOM P54 Series, Technical Manual

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Settings P54x/EN ST/La4
MiCOM P543, P544, P545, P546
(ST) 4-41
ST
1.3.14 Thermal overload
The thermal overload function within the MiCOM P54x is capable of being selected as a
single time constant or dual time constant char
on the type of plant to
b
acteristic, dependent
e protected.
Setting range
Menu text Default setting
Min. Max.
Step size
Characteristic Single Disabled, Sing l le or Dua
Setting for the operating characteristic of the thermal overload element.
Thermal Trip
1 x

n 0.08 x

n 4 x

n 0.01 x

n
Sets the maximum full load current allowed and the pick-up threshold of the therma
characteristic. l
Thermal Alarm 70% 50% 100% 1%
Setting for the thermal state threshold corresponding to a percentage o
at which an alarm will be generated. f the trip threshold
Time Constant 1 10 minutes 1 minute 200 minutes 1 minute
Setting for the thermal time constant for a singl irst e time constant characteristic or the f
time constant for the dual time constant characteristic.
Time Constant 2 5 minutes 1 minute 200 minutes 1 minute
Setting for the second thermal time constant for the dual time constant characteristic.
1.3.15 V
U
i
oltage protection
nder and overvoltage protection included within the MiCOM P54x consists of two
ndependent stages. The measuring mode (ph-N or ph-ph) and operating mode (any phase
o gurable as a combination between Stage 1 and Stage 2, therefore
a ependent operation for each stage.
S lected MT, DT or Disab thin the
V<1 function
cell. Stage 2 is
D
Two re required.
nge
r 3 phase) are confi
llowing completely ind
tage 1 may be se as ID led, wi
T only and is enabled/disabled in the
V<2 status
cell.
stages are included to provide both alarm and trip stages, whe
Setting ra
Menu text Default setting
Min. Max.
Step size
UNDERVOLTAGE
V< Measur't. Mode V<1 & V<2 Ph-Ph
V<1 & V<2 Ph-Ph
V<1 & V<2 Ph-N
V<1Ph-Ph V<2Ph-N
V<1Ph-N V<2Ph-Ph
N/A
Sets the combination of sured input voltage that will be us the unde e
ing will
visible but will not affect the ope e sta is enab
mea ed for rvoltag
elements.
Note:
If any stage is disabled, the associated text in the setting menu cell sett
remain ration of th ge that led.
V< Operate Mode
V<1 & V<2 Any Ph
V<1 & V<2 Any Ph
V<1 & V<2 3Phase
V<1AnyPh V<2 3Ph
V<1 3Ph V<2AnyPh
N/A
Setting that determines whether any phase or all three phases has to satisfy the
undervoltage criteria before a decision is made.
Note:
If any stage is disabled, the associated text in the setting menu cell setting will
remain visible but will not affect the operation of the stage that is enabled.