Neuberger RPM 370 Bedienungsanweisung Seite 6

D e r S p a n n u n g sw ert d e r je w e il s e in g e s t e llt e n G r o b s tu fe
kann m it d e r F e in r e g e lu n g n ie m a ls ü b e r s c h r it t e n w e r d e n .
D ie H eizsp a n n u n g w ir d d u r c h ein P r ä z i s i o n s - D r e h s p u l ­
in s tr u m e n t (0 , 1 m A ) m it G le ic h r ic h t e r ü b e r w a c h t . D as
M e ß in s tr u m e n t a r b e it e t a ls V o ltm e t e r m it fo lg e n d e n M e ß ­
b e r e ic h e n : 2 - 4 - 8 -
D ie B e r e ic h u m s c h a ltu n g e r fo lg t a u to m a tis c h m it d e r S pan ­
n u n g sw a h l. D e r je w e il s e in g e s c h a lt e te S p a n n u n g sb e re ich w ir d
in e in e m A u s s c h n itt d e r F r o n tp la tte ü b e r d e m S tu fe n s c h a l­
t e r a n g e z e ig t. Is t z . B . d ie G r o b s tu fe 120 V o lt e in g e s t e llt ,
so e r s c h e in t in d e m F e n s t e r d e r A u fd r u c k " 2 x 1 0 0 ", d .h .
e s w ir d a u f Skala 0 -2 a b g e le s e n und m it 100 m u lt ip liz ie r t .
D e r V o lla u s s c h la g d e s In s tr u m e n ts b e d e u te t a ls o 200 V o lt.
B e i d e r Ü b erw a ch u n g d e r H eizsp a n n u n g m uß d e r u n te r d e m
M e ß in s tr u m e n t b e fin d lic h e K ip p s c h a lte r n a ch lin k s in S te l­
lung " V o l t " steh e n .
F ü r d ie G r o b stu fen v o n 25 - 200 V o lt kann au ch d e r H e i z ­
s t r o m d e r zu p r ü fe n d e n R ö h r e n ü b e r w a c h t w e r d e n , w enn
d e r e rw ä h n te K ip p s c h a lte r n a ch r e c h t s in Stellu ng " 0 , 4
A m p . " , g e s c h a lt e t w ir d . D a s M e ß in s tru m e n t is t dann
a ls S t r o m m e s s e r m it e in e m M e ß b e r e ic h v o n 0 ,4 A m p .
V o lla u s s c h la g in d en H e i z s t r o m k r e is e in g e s c h a lt e t . U m
b e i R ö h r e n m it k le in e m H e iz s t r o m , (z . B . 50 m A ) e in e
g en ü g en d g e n a u e A b le s u n g d e r In s tr u m e n te n s k a la zu
e r m ö g lic h e n , kann m it H ilfe e in e s n e b e n d e m K ip p s c h a l­
t e r a n g e o r d n e te n D ru c k k n o p fe s m it d e r B ez e ich n u n g
"G e d r ü c k t 0, 2 A m p . " d e r M e ß b e r e ic h auf 0, 2 A m p .
V o lla u s s c h la g u m g e s c h a lte r w e r d e n .
D ie M e ssu n g d e s H e iz s t r o m e s is t n ic h t m ö g lic h , w en n d e r P r ü f ­
s c h a lt e r (r e c h t s n e b e n d e m H a u p tin stru m e n t) in Stellu ng " F P "
(H e iz fa d e n -P r ü fu n g ) ste h t, da in d ie s e r S ch a lte r Stellung k ein e
H eizsp a n n u n g an d e r R ö h r e lie g t .
E s is t a ls o n o tw e n d ig , b e i a lle r R ö h r e n , e in s c h lie ß lic h d e r s o ­
gen a n n ten " A l l s t r ö m - R ö h r e n " , d ie H eizu n g z u e r s t sp a n n u n g s­
m ä ß ig e in z u s t e lle n und d ie H e i z s t r o m - K o n t r o ll e e r s t n a ch v o l ­
l e r E r w ä r m u n g d e r R ö h r e v o r z u n e h m e n . D ie s i s t sc h o n d e s ­
h a lb z w e c k m ä ß ig , da A lls t r o m - R ö h r e n b e k a n n tlich e r s t n a ch
v o ll e r E rw ä r m u n g ih r e n v o r g e s c h r ie b e n e n H e iz s t r o m an n eh m en .
B e i den G r o b s tu fe n b is 20 V o lt i s t d ie H e iz s t r o m - M e s s u n g m it
d e m e in g e b a u te n M e ß in s tr u m e n t n ic h t m ö g lic h . H ie r w ir d b e i
B etätig u n g d e s K ip p s c h a lt e r s " V o lt - 0 , 4 A m p . " in Stellung
" 0 , 4 A m p . " d a s In s tr u m e n t le d i g lic h a ls V o lt m e t e r a b g e ­
s c h a lte t. U m d ie G r o b s tu fe n 25 - 200 V o lt
H e iz s tr o m ü b e r w a c h u n g m ö g lic h i s t , s c h o n ä u ß e r lic h zu k e n n ­
z e ic h n e n , sin d d ie s e G r o b s tu fe n s o w ie d ie K ip p s c h a lte r S te l­
lung 0 ,4 A m p . und d ie D r u c k k n o p fb e z e ich n u n g " G e d r ü c k t 0 ,2
A m p . " d u r c h r o t e G r a v ie r u n g h e r v o r g e h o b e n .
4
20 - 40 - 80 - 200 V o lt.
b e i d en en au ch die