Micom ALSTOM P341, Technical Data Sheet

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P341 Technical Data Sheet
28
P341 Software versions 36 & 71J
Thermal overload
Thermal: Disabled/Enabled
Thermal I>: 0.50…2.50 In
Thermal Alarm: 20..100%
T-heating: 1…200 minutes
T-cooling: 1…200 minutes
M Factor: 0…10
The thermal time characteristic is given by:
t =
τ
log
e
(
Ι
eq
2
-
Ι
P
2
)/(
Ι
eq
2
- (Thermal
Ι
>)2)
t =
τ
. log
e
((K
2
-A
2
)/(K
2
-1))
Where:
K =
Ι
eq
/Thermal
Ι
>
A =
Ι
P
/Thermal
Ι
>
t =Time to trip, following application of the
overload current,
Ι
τ
=Heating time constant of the
protected plant
Ι
eq
= Equivalent current
Thermal
Ι
> = Relay setting current
Ι
P
= Steady state pre-load
current before
application of the
overload
Ι
eq
=
√
(
Ι
12 + M
Ι
22)
Ι
1 = Positive sequence
current
Ι
2 = Negative sequence
current
M = A user settable
constant proportional
to the thermal
capacity of the
machine
Earth fault
IN1>1 Function:
Disabled
DT
IEC S Inverse
IEC V Inverse
IEC E Inverse
UK LT Inverse
RI
IEEE M Inverse
IEEE V Inverse
IEEE E Inverse
US Inverse
US ST Inverse
IDG
IN1>1 Directional
Non-Directional
Directional Fwd
Directional Rev
IN1>1 Current Set: 0.08…4.00 In
IN1>1 IDG Is: 1.0…4.0 In
IN1>1 Time Delay: 0.00…200.00 s
IN1>1 TMS: 0.025…1.200
IN1>1 Time Dial: 0.01…100.00
IN1>1 K(RI): 0.10….10.00
IN1>1 IDG Time: 1.00...2.00
IN1>1 Reset Char.: DT/Inverse
IN1>1 tRESET: 0.00…100.00 s
IN1>2 as IN>1
IN1>3 Status:
Disabled
Enabled
IN1>3 Directional:
Non-Directional
Directional Fwd
Directional Rev
IN1>3 Current Set: 0.08…32.00 In
IN1>3 Time Delay: 0.00…200.00 s
IN1>4 as IN>3
IN1> Blocking:
Binary function link string, selecting which
ground overcurrent elements (stages 1 to 4)
will be blocked if VTS detection of fuse
failure occurs.
IN1> Char Angle: -95… +95
°
IN1> Polarization:
Zero Sequence
Neg. Sequence
IN1> VNpol Set:
0.5…80.0 V (100/110 V)
2…320 V (380/480 V)
IN1> V2pol Set:
0.5…25.0 V (100/110 V)
2…100 V (380/480 V)
IN1> I2pol Set: 0.08…1.00 In
The IDG curve is commonly used for time
delayed earth fault protection in the Swedish
market. This curve is available in stage 1 of
the Earth Fault protection.
The IDG curve is represented by the following
equation:
t = 5.8 - 1.35 loge
⎝
⎜
⎛
⎠
⎟
⎞
Ι
Ι
N > Setting in seconds
Where:
Ι
= Measured current
Ι
N>Setting = An adjustable setting
which defines the start
point of the
characteristic
Although the start point of the characteristic is
defined by the “
Ι
N>” setting, the actual relay
current threshold is a different setting called
“IDG
Ι
s”. The “IDG
Ι
s” setting is set as a
multiple of “
Ι
N>”.
An additional setting “IDG Time” is also used
to set the minimum operating time at high
levels of fault current.