Allis-Chalmers BWX-6637-5, Инструкция

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CAUT IO N :
A L L
S E LECT I ON KNOBS ARE EQU I PP E D W I TH SHAFT LOC KS TO
ENS URE PERMAN ENCE
O F
S ETT I NG S .
TURN I NG A KNO B ON
A
LO C K E D SHAFT W I LL CAUS E LOS S
O F
CAL I B RAT I ON . TH E
S E CT I ON O N MA I NTENANCE D E S C R I B E S
H OW
T
O
R E STORE
C A L I B RAT I ON I
F
TH I S SHOULD
HA P P E N .
Se l ec t ion
The th r e e knobs a r r a n ged v e r t i ca l l y on the r i gh t hand s i de o f t h e
s ta t i c t
r
i p d e v i ce ( F i gu re 7) a re f o r s e l ec t i on o f t h e c
u r
r en t a t
wh i ch
a
t i m e de l a y t r i pp i ng ope r a t i on w i
I I
s t a r t
.
Th i s
I s
t h e
p i ck-up
c u r r e n t . O n e knob I s p r ov i de d f o r e a c h p h
a
s e ( e
x
c e p t Mod e l s
AG , DG , whe re t h e m i d d l e knob
I
s u s e d t o s
e
l
e
c t g round c u r r e n t p i c k ­
u p)
•
T h e
p i
c
k
-
u
p s e l ec t i on
d
i
a
l s a re ma rked w i t h t h e l e t t e rs "A" t h r ou gh
"E1 1•
The p i c k - u p c
u
r
r
e n t
def i ned
by e a c h l e t t e r I s l i s t ed on t h e
c i
r
cu
i
t
b rea ke r
ra t i ng p l a t e ( F i g u re
7A
)
.
Th i s I s t h e m i n i mum
p r i ma r y c i rc u i t c u r re n t wh i ch w l
1 1
ca u s e t h e c i r c u i t b reake r to
ope n .
E XAMP LE :
A c
i
r c u i t b rea ke r has a
r
a
t
i
n
g p l a t e a s s hown
i n
F i g u r e ]A . The p i c k - u p s e t t i n g s a re a t p
o
i
n t
1 1N 1 •
The r e f o r e , t he c i r c u i t w i
11
ca r r y u p t o
200
Amp �
w i t ho
u
t
t r i pp i ng �he
c i r c u i t b r ea ke r . Above
200
Amps
a
t r i p
o p e r
a
t i on w l I I oc c u r .
The p i c k- u p
s
e
l
e c t
i
on i s con t i nuous a n d may b e s e t be tween ma r ks i f
des i red . U s u a l p ra c t i ce i s to s e t a.l l p i c k - u p knobs a t the s ame
ma rk , b u t t h i s i s n o t neces s a ry a n d d i f f e re n t p h a s e s c a n have
d i f f e ren t p i c k - u p s e t t i ngs .
The r a t i
n
g of t he c i r c u i t b r e a k e r d e pends s o l e l y on t he p
r i
ma r y
c u r re n t t ra ns f o rme r s s
e
l
e
c
t e
d
f o r
t h e
a pp l i ca t i on , a n
d i s l i m i t e d
on l y
b y t h e c i rc u i t b r eake r f rame s i
ze
.
T h e r a t i n g
o f a c i rc u i t
b r eake r ma y
be c
h a n g
e d
i f des i r ed me r e l y b y r e p l a c i ng
the
c u r r e n t
t ra n!. f oru.e r s
a n
d
t h e b r e a ke r ra t i n g p l a t e .
N
o t h i n y c h a n g
e
s on t he
S t. d t i t.: t r i p dev l c.�
o r
o t h e r
b r eake r
c omponen t s . F i g u r e
7A
shO\�!>
b rea k� r
r
a
t
i
n g s ava l l a b l e
w i t h va r i ous
c u r ren t
t r a ns f o rme r s .
D .AMP L t: : l h�
b r e a k e r
r e p r e s e n ted b y
t h e
r
a
t
i
n
g
p l a t e I n
f i gu re 7A i s
cha nged
t o
have 60 0 m
a
x
i m u
m
ra t ed Amp s
( t h u s A
•
300 ,
B
•
3 7 5 , C
•
450 ,
D
•
5 2 5 ,
E -
6oo) .
The p i c k - u p s e t t i ngs a r e s t i l l on
"A" .
The c i r c u i t
w i l l
now
c a r r y up
to 300 Amps and
w i I I t ri p on a ny ­
t h i n g a bove
300
A
m ps i n t h e p r i ma ry c i r cu i t .
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