Maxwell Digital Multimeters 25302 User Manual page 5

set the switch to the highest possible range and go
backwards until you reach the correct setting.
If only a „1" is displayed on the screen, it signals
•
overload. Switch to a higher range.
Maximum inward current may be 200mA or 20A based
•
on the selected connector. (The test time may be 10
seconds max.) Currents too high may melt the fuse
which then needs to be replaced. The 20A range is not
protected!
Resistance measuring
Connect the black wire to the „COM" and the
•
red one to the „V/ Ω" connector.
Set the function switch to the desired
•
resistance range.
Touch the wires to the measured circuit
•
paralelly.
Note: make sure that the measured circuit is
not under power!
The maximum overload capability for the
•
connector is 250V RMS (for maximum 10
seconds).
Note:
If the measured resistance value is over the maximum
•
threshold and the device signals overload („1"), select a
higher range. When measuring above 1MΩ it may take
a few seconds for the device to stabilize the displayed
value. This is completely normal for such resistors.
If you do not connect a resistor to the connector (or
•
there is a break) the display will show „1".
If you are measuring a resistor that is part of a circuit
•
make sure that the circuit is not under power and all
capacitors are discharged.
Do not connect inward voltage to the device as it may
•
lead to damage to the inside circuits.
Capacity measuring
Set the function switch to F position.
•
Connect the measuring sensor to the „mA", and
•
„COM" connectors.
• Connect the measured capactitors connectors
to the sensor. Pay attention to the correct
polarity.
Note:
If the measured value exceeds the maximum value of
•
the selected range and the device signals overload („1"),
select a higher range.
Unit: 1 nF=10-3 μF or 1000 pF
•
Do not connect external voltage or current to the
connector! Turn off the power and discharge the
capacitors before measuring. Also discharge the
electrolyte capacitors before measuring!
Diode and continuity test
Connect the black measuring wire to the
•
„COM" and the red to the „V/ Ω" connector.
(Note: the polarity of the red wire is +).
Set the function switch to
•
Touch the wires to the diode's connectors.
•
The screen shows the opening voltage of the
diode.
Connect the wires to two points of the circuit.
•
If the resistance is below 90Ω the device
beeps.
Note:
If you do not connect a unit to the connectors (or there is
•
a break) the display will show „1".
During the test 1mA current goes through the diode.
•
The display shows the opening voltage of the diode
•
in mV and overload if the diode is connected with the
polarity reversed.
Temperature measuring
• Set the function switch to °C position.
• Connect the temperature measuring sensor to
the connectors (pay attention to the polarity,
the black is „-") and touch the other end to
the measured object. The display shows the
measured value in °C.
Transistor hFE test
Set the function switch to hFE position.
•
Determine if the transistor is NPN or PNP and place
•
it in the proper connector.
The amplification factor of the transistor is
•
displayed on the screen.
I = 10 μA, V = 2,8 V
BC
Frequency measuring
Connect the measuring wire or the shielded cable
•
to the „COM" and „V/ Ω/Hz" connectors.
Set the function switch to „1 MHz" position and
•
touch the wires to the signal source.
Note:
Do not measure frequency at a voltage exceeding 250V RMS!
•
In noisy environment it is advised to use a shielded cable for
•
measuring small values.
Avoid touching the circuit when measuring high voltage!
•
Data hold function
Pressing the „HOLD" button the displayed value on
•
the screen gets held. To turn the function off press
the button again.
Automatic power off and standby
15 minutes after the last measurement the device
•
powers off automatically.
EN
User Manual
position.