Dc And Ac Voltages (V Dc And Ac); Decibels (Db) - Chauvin Arnoux C.A 5005 Notice De Fonctionnement

3 - DC AND AC VOLTAGES
I Connect the leads to the multimeter and connect in parallel to the
circuit to be tested.
I When the order of magnitude is not known, place the switch on the
highest range then progressively lower to the appropriate range.
I To get the voltage in V, multiply the value read on the appropriate
scale by the reading cœfficient shown in the table.
V DC
(1)
100 mV 1 V
Scale 100 100
Reading
(2)
x1 x0,01
cœfficient
Internal
2 kΩ 20 kΩ 63,2 kΩ 200 kΩ 632 kΩ
(3)
resistance
(4)
Accuracy 2,5 %
Permitted
440 V
overload
(1) Common to the 50 µA range
(3) Specific R: 20 kΩ/V, except range 1000 V-R = 6.32 kΩ/V
(4) In % of the end of scale
V AC
10 V 30 V
Scale 100 30
Reading
x0,1 x1
cœfficient
Internal
63,2 kΩ 200 kΩ 632 kΩ 2 MΩ 6,32 MΩ
(1)
resistance
(2)
Accuracy 3 %
(3)
Bandwidth 100 kHz 50 kHz 25 kHz
Permitted
1000 V
overload
4 - DECIBELS
I I I I I Reminder. The measurement of an AC voltage can be expressed
in decibels (symbol dB). The decibel is the ratio of two quantities or
levels. Level N, in dB, of a voltage U has the mathematical expression:
N dB) (
U is the reference voltage of 0.775 V AC for a power P
o
on a load of 600 Ω.
I I I I I Use. Zero level of the red scale in dB corresponds to Uo = 0.775
for the 10 V AC range. The reading is direct in dB for the 10 V AC range
from 0 to +22 dB. For the other ranges, it is possible to read in dB (near
value) by adding respectively:
+10dB on the 30 V AC range
+30dB on the 300 V AC range
3 V 10 V 30 V 100 V 300 V 1000 V
30 100 30 100
x0,1 x0,1 x1 x1
2 MΩ 6,32 MΩ 6,32 MΩ
1,5 %
(5)
1000 V
(2) Direct reading in mV
(5) For 15 seconds
100 V 300 V 1000 V
100 30 100
(1) Specific R:
x1 x10 x10
(2) In % of
2,5 %
(3) From 20 Hz to ...
1 kHz
(4) For 15 seconds
(4) (4)
1500 V
( )
= 20 log U U
10 0
+20dB on the 100 V AC range
+40dB on the 1000 V AC range
30 100
x10 x10
(5)
1500 V
6.32 kΩ/V
the end of scale
of 1 mW
o
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