Conrad 12 79 49 Bedienungsanleitung Seite 12

REL Press button "F1" to set the present indication to "0", i.e. all the fol-
lowing measurements are with reference to "0 Ohm". The differen-
ce from the set "zero point" is displayed. During this function the
symbol "REL" flashes. To switch off the function, press button F1
once (flashing stops, REL function off).
To activate acoustic continuity testing, press button F2. The continui-
ty range includes up to 400 Ohm resistance. Because of this, the
automatic range selection symbol "AUTO" disappears from the scre-
en. Instead of this the symbol "RANGE" appears in the screen, as for
manual range selection. However, changing the measurement ran-
ges is not possible. For continuity resistances below 40 Ohm, a conti-
nuous acoustic signal sounds.
nS Press button F3 to activate the reciprocal value function, which
however only functions in the upper MOhm range, since the recipro-
cal value of a resistance is measured in the MOhm range in nS (nano-
Siemens or nano-Mho). While the function is active, the symbol nS
flashes. This function is switched off by pressing button F3 again
once; the flashing stops and the function "nS" switched off.
P-H In the "Peak Hold" function, the highest ("MAX") and lowest
("MIN") resistance values occurring at any time are captured and
indicated. The present measured value always appears In the upper
line of the display (the Peak Hold function can only be called in digi-
tal mode). In the basic menu press button "F4". The measurement
can be interrupted with button F3 ("Pause") and restarted with but-
ton F2 ("Run"). To quit the P-H function, press button F4 again.
Attention!
Pressing the 'MODE" button for a graphical display is not possible.
Notes!
If resistors are to be measured which are built into a circuit in which
transistors/diodes are present, the 400-Ohm range test voltage is suffi-
cient to cause current to flow through these semiconductors. Hence the
measured values can be distorted.
The resistance of the test leads can normally be ignored (approx. 0.1 to
0.2 Ohm). However, even this low value can lead to inaccuracies in the
400 Ohm measurement area.
22
When resistance measurements are performed, take care that the mea-
surement points which are to be touched with the test probes are free
from dirt, oil, solder flux or similar. Such conditions can distort the mea-
sured value.
Should "OVER" appear in the display, the measurement range has been
exceeded or the circuit being measured is open-circuit.
Do not measure charged capacitors because a possible discharge may
damage the measuring instrument.
28.0
RS232
REL P-H
5.5 Measurement of diodes and capacitors „
Attention!
Discharge every capacitor before connecting it to the measuring instru-
ment.
When short-circuiting capacitors, high-energy discharges can occur. Take
care in areas where dust, inflammable gas, fumes or liquid is present or
can occur! Danger of explosions!
Do not touch the connectors of capacitors with voltages over 35 VDC or
25 VAC. Caution - danger to life!
Carry out no measurements on capacitors built into circuits or parts of
circuits.
For the measurement of diodes and semiconductors or capacitors up to
4000 µF (= 4 mF) proceed as follows:
a) Set the rotary switch to "
b) Connect the black test lead to the "COM" measuring instrument
socket and the red test lead to the "-I(-•-I<-•-mA•SIG•AUX•LOGIC"
socket.
HI-Z
mVdc
RANGE 400mV
DC dB
mV/Hi-Z
"
"
23