2-10
IM DLM3054-03EN
2.4 Connecting Probes
WARNING
• When connecting a device under measurement to the instrument, be sure to turn off the
device. It is extremely dangerous to connect or disconnect a measuring lead while the
device under measurement is on.
• Do not apply input voltage exceeding the maximum input voltage, withstand voltage, or
allowable surge voltage.
• To avoid electric shock, be sure to ground the instrument. Furthermore, connect the ground
of the probes or input connectors to the ground potential of the device under measurement.
The ground of each signal input terminal (input connector) of this instrument is common
with the instrument’s protective ground (see the block diagram in appendix 3). Do not apply
floating potential signals to the input connector ground. This is extremely dangerous as
doing so will cause a short to the ground potential. Use a differential probe when measuring
floating potential.
• Avoid continuous connection under an environment in which the surge voltage may occur.
• If over-range is indicated,* the instrument may be receiving a voltage higher than the
observed waveform or measured waveform values. To prevent electric shock, change
the vertical scale with the SCALE knob so that the entire amplitude of the waveform is
displayed within the waveform display area, and check the input voltage level.
* If the input coupling is set to AC, the over-range indicator may not be displayed. For details, see
section 1.1, “Input Coupling,” in the User’s Manual, IM DLM3054-02EN.
Over-range indication
CAUTION
• The probe interface terminals are located near the input terminals on this instrument. Do
not short the probe interface terminals. When you connect a probe, make sure to prevent
an excessive voltage caused by static electricity, etc., from being applied to the probe
interface terminal, as this may damage the terminal.
• The maximum input voltage for 1 MΩ input is 300 Vrms or 400 Vpeak when the frequency
is less than or equal to 100 kHz. Applying a voltage greater than either of these limits may
damage the input section. If the frequency is above 100 kHz, damage may occur even
when the voltage is below this value.
• The maximum input voltage for 50 Ω input is 5 Vrms or 10 Vpeak. Applying a voltage
greater than either of these limits may damage the input section.
• For information about how to handle a probe, refer to the user's manual that came with the
probe.
