Db Measurements In Relative Reference Mode (Zero Set) - Philips pm2521 Operating Manual

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d B M E A S U R E M E N T S I N R E L A T I V E R E F E R E N C E M O D E ( Z E R O S E T )
-
M e a s u r e t h e a l t e r n a t i n g v o l t a g e i n t h e d B f u n c t i o n a s d e s c r i b e d a b o v e .
D e p r e s s p u s h b u t t o n d B ( V - ) , Z E R O S E T a g a i n .
R e m a r k :
T h e d i s p l a y w i l l b e h e l d f o r o n e s e c o n d a n d a Z w i l l a p p e a r o n t h e r i g h t - h a n d s i d e o f t h e d i s p l a y . T h e v a l u e
which is on the display during this one second is the relative reference value. After this one second the
d i s p l a y j u m p s t o z e r o a n d t h e i n d i c a t i o n Z S ( Z E R O S E T I w i l l a p p e a r o n t h e d i s p l a y . T h e P M 2 5 2 1 h a s n o w
been switched to the relative reference (ZERO SET) mode. In the relative reference mode the PM2521
switches to automatic ranging. Each subsequent reading will indicate the positive or negative deviation from the
relative reference value.
T o l e a v e o Í t h e d B f u n c t i o n , d e p r e s s p u s h b u t t o n d B ( V - ) Z E R O S E T a g a i n .
R e m a r k :
Take care that the maximum input voltage of 600 V rms is not exceeded. 600 V rms = +57.8 dB.
However, in relative reference mode the relative reference value must be added with the measured value.
6.4. 1.4. Direct current measurements (A-)
-
S e l e c t f u n c t i o n A -
w i t h t h e f u n c t i o n s e l e c t o r .
-
S e l e c t t h e m a n u a l o r a u t o m a t i c r a n g i n g m o d e w i t h p u s h b u t t o n A U T O / M A N * .
R e m a r k :
M a n u a l r a n g i n g i s i n d i c a t e d w i t h a * o n t h e d i s p l a y .
In automatic ranging mode the up level is 2020 and the down level is 0180.
S e l e c t i n m a n u a l r a n g i n g m o d e t h e c o r r e c t r a n g e w i t h p u s h b u t t o n U P o r D O W N .
R e m a r k :
A v a i l a b l e r a n g e s a r e : m A t e r m i n a l
O . 2 A - 1 0 t e r m i n a l
2.000 pA
200.0 mA
20.00 sA
2.000 A
200.0 pA
20.00 A
2.000 mA
20.00 mA
Overload is indicated with OL on the display (Display > 2100).
ln range 20 A overload is also indicated at 21.00 A. However, the maximum continuous input current is 10 A.
- C o n n e c t t h e c u r r e n t s o u r c e t o t h e 0 a n d m A o r O . 2 A - 2 0 A t e r m r n a r
R e m a r k :
The polarity indicated is the polarity of the A terminals with respect to the 0 terminal.
CuÍrent up to 31.6 A can be measured with shunt PM 9244. Befer to chapter 6.4.2.2.
Due to the measuring method the display does not indicate zero when the input is short circuited.