Allis-Chalmers BWX-6637-5, Инструкция

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B .
OF S TAT I C TR I P
T h
e
s
e I ns t r uc t i on s d e s c r i b e f o u r
mod e l s
of
s ta t i c t r i p
d
ev i
c e
s
.
A I I a r e
s i m i
J a r I n m a
n y res pec t s a n d
d i f f e r
on l y i n t
h
e k i n d of end u s e
func t i on t h a t t hey
p rov i de . A l l
u s e
the s ame
c u r r
en
t t r ans forme r
i
n
p
u t s and p rov i d e
ou t p u t s
i gn
a
l
s
to t h e m a g n e t i c
l
a t
c
h
re l ease as
p r ev i ous l y
des c r i be d .
D ua l
t�ode l A I
Fu r n i s h ed w i t h
one
non-adj us t a b l e c u r r en t - t i me c u rv e . The
c u rve may be
e i t
h
e r for t he
m i n i mum ,
the
i
n t e r
m
e
d
i a t
e
,
or
t h
e
max i mum
c u r v e
as s hown
I n
F i g u re ]E .
T i me
de l ay
up to f i f t een
i
i
m
e
s p i ck-up
i s
s t a n d a r d , a s
I s
i ns t a n t aneous
t
r i
p
p
i
n
g be tween f i ve a nd f i f t een t i mes p i c k - up b y ad
j
u s
t
m
e
n t
.
I t mon i tors t h e c u r r e n t i n e
a
c
h
o f t h e t h ree phases .
D u a l Mode l
AG
S ame a s t h e Hode l A I except t h a t the c i r cu i t I s a r r a n ged to mon i t o r c u r r e n t
I n
two p
h
a s
e
s
a n d
cu
r
r
e
n
t i n t he neu t ra l of t h e
p r i ma ry
c
u
r
r e
n t
t rans f o rme r s .
Th i s
dev i ce i s
thus
a b l e t o p rov i de n o rma l ove r l oa d and
s
h o
r
t c i r c u i t
p
r
o
t e c t i o n
,
a n d a l so to d e t e c t g round fa u l t c u r r e n t s
as
l ow
a s
20%
o f
the
c u r re n t
r e
q
u i r
e
d t o o
p
e
r
a t e t he p h a s e c i rcu i t s .
Se l ec t i ve
M o
d e
l
0
Th i s s ta t i c ove r c u r re n t t r i p d ev i ce i s f u r n i s hed w i th t
h
r
e
e
l on g t i me d
e l
a
y
c u r v e s and t h ree s ho r t t i me d e l ay
c u rves , any
c
o
m
b
i n
a
t i
on
s
of wh i ch may be
s e l ec ted b y
s et t i ngs
on t h e
f ron t
pl
a
t
e of t h e dev i ce . Se l ec t i v i ty
be tween
c oo r d i na ted c
i
r
cu i t b reake r s can be ma i n t a i ned t h roughou t the f u l l i n t e r ­
r u p t i ng r a n ge o f the c i rc u i t b r eakers .
T h e
M o d
e
l 0 d ev i c e mon i t o r s
t he
c u r re n t s
i n e
a
ch
of
t h e t h ree pha s e s . The a r ra ngemen t of the c u r r
e
n t
-
t i me
c u r v e s i s s h own
i n
F
i
gu
re 70 .
Se l e c t i ve
Mod e l
OG
Same
as the
Mode l 0
ex
c
e
p
t t h a t t he c i
r
c u i t I s a r ranged to mon i t o r c u r
r
e n t
i n
two p
h a
s
es and c u r r e n t i n the n
e
u t
r
a l of
the pr i ma ry
c u r ren t
t r ans forme rs .
T h i
s
dev i ce i s t h u s ab l e to p rov i de no rma l ove r l oa d and s ho r t c i r cu i t
p r o t ec t i on , a n d a l s o to d e t e c t g round fa u l t c u r r e n t s as l ow a s
20%
of t h e
c u r ren t r e
q
u
i r e d t o ope r a t e t h e p ha s e c i r c
u
i ts
.
T h r·ougho u t t h e
tex t
a ny r e fe rence to s t a t i c t
r
i p dev i ce
-
I .
A- I I s a I s o a p p l l c a b l e to
A-2
AG i s
a
I s o
a pp l i ca b l e t o
AG - 1
0
i
5 a
I s o a p
p
l
i
c
a
b
l e
t o 0 - 1
S E LECT I O N O F S ETT I NGS
The s t a t i c ov c �c u r ren t t r i p dev i ces have
a
n u
m
b e r of knobs a n d sw i tches
wh i ch can be a r ranged to s e l ec t
t h e
s pe c i f i c c o nd i t i
o
n
s
t h a t w i l I c a u s e
the
c i r
c
u i
t
b reake r t o
open .
Th e s e l ec t i on o f
s e t t i n g s
I s us ua l l y
m
a
d
e
when t h e c i r cu i t b re a k e r
i s
p l aced i n s e rv i ce , a n d w i l l n o t r e qu
i r
e l a te r
chan ges
un l es s l oad cond i t i on o r o t h e r p r i ma ry c i r c u i t c h a n ges a r e mad e .
The f o l l ow i n g pa r a g r a p h s d e s c r i be
t h e va r i ous s e l ec t i ons tha t m
a
y
be
made .
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