IM3G-VX
Doc. N° MO-0068-ING
Rev.
1
Pag.
8
of
36
Copyright 2010 - Microener
2.3.4 - Voltage controlled overcurrent
If the para
meters I>/U and/or I>>/U are set to “ON” the voltage controls is active respectively
for the level I> and/or I>>. The actual pick-up levels (I>,I>>) variate in respect to the programmed
levels ([I>] , [I>>]) proportionally to variation of the voltage according to the curve herbelow
I
[I ]
,
I
[I
]
Actual pick - up level
[Set pick - up level]
U
[Uns]
Actual voltage
[Rated input voltage]
The voltage ratio is measured on each phase
Ex
3
[Uns]
and the smallest among the values is
used in the algorithm. Practically in the zone between 0.2 and 0.8 Uns, the relay operates as
underimpedance protection when
Zx
Ex
Ix
[Uns]
3[I ]
,
[Uns]
3[I
]
.
2.3.5 - F46 - Current unbalance : Measurement of RMS Negative Sequence Current I
2
F1 46
: I
2
2
t = K (adiabatic heating)
-
Generator’s continuous I
2
rating :
1Is
= (0.05-0.5)Ib, step 0.01Ib
Setting
1Is
= Dis blocks function’s operation
- Time multiplier :
Ks
= (5-80)s, step 1s ;
Ks
= Trip time when I
2
= I
b
- Trip time delay
t
Ks
(I / I )
h
2
b
2
; Heat accumulation only operates if I
2
[1Is]
- Cooling time from trip level to the status corresponding to the operation at I
2
=[1Is] :
tcs
= (10-1800)s, step 1s
Cooling time
t
[tcs]
Ks
I
I
t
l
2
b
2
; t
l
= [tcs] when
I
I
t
Ks
2
b
2
Cooling only takes places if
I
I
1Is
2
b
(see curves TU0312 §19)
Содержание IM3G-VX
Страница 29: ...IM3G VX Doc N MO 0068 ING Rev 1 Pag 29 of 36 Copyright 2010 Microener 19 TIME CURRENT CURVES F51 TU0311 Rev 0...
Страница 30: ...IM3G VX Doc N MO 0068 ING Rev 1 Pag 30 of 36 Copyright 2010 Microener 20 I2 t CONSTANT ELEMENT F46 TU0312 Rev 0...
Страница 31: ...IM3G VX Doc N MO 0068 ING Rev 1 Pag 31 of 36 Copyright 2010 Microener 21 THERMAL IMAGE CURVES TU0325 Rev 0...
