Decibels; Dc And Ac Currents - Chauvin Arnoux C.A 5011 Manual De Instrucciones

„ 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:
U is the reference voltage of 0.775 V~ for a power
0
P of 1 mW on a load of 600 W
0
„ Use. Zero level of the red scale in dB corresponds to
U =0.775 V for the 4 V ~ range. The reading is direct in dB for the 5 V ~ range, on
0
analogue only, from -20 to +16 dB.
The digital display indicates the value of the voltage in volts.
For the other analogue ranges:
„ 500 mV : subtract -20 dB
„ 50 V : add +20 dB
„ 500 V : add +40 dB
„ 1000 V : unusable
Always switch off the circuit to test before connecting the multimeter to the
circuit. If the "Fus." light comes on, change the faulty fuse(s) (Reminder: minimum
voltage of 100 V).
Connect the leads to the multimeter and connect in series to the circuit with:
- the red lead in the «μmA», terminal, up to 1 A
- the red lead in the «10 A», terminal, from 1 A to 10 A
„ When the order of magnitude is not known, place the switch on the highest range
then progressively lower to the appropriate range.
„ Analogue reading: to get the current in mA, mA or A, multiply the reading on the
appropriate scale by the reading coefficient shown in the table.
„ Digital reading: if necessary, press the following keys
-
- MAX
- HOLD to hold in memory
-

5. DECIBELS

6. DC AND AC CURRENTS

for the rms value (See in CH. 3)
for the maximum value
for display backlighting
19