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3.13 Connecting Wires to the 16-CH Voltage Input
Module
To measure voltages with the 720220
(
16CH VOLT
), connect wires to the terminal block.
WARNING
• When connecting a device under measurement to the instrument, be sure to turn off the
device. It is extremely dangerous to connect or remove wires while the device under
measurement is on.
Precautions to Be Taken When Using the Modules
• 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.
• To prevent the possibility of electric shock, be sure to fasten the module screws. Otherwise,
the electrical protection function and the mechanical protection function will not be activated.
• Do not leave the instrument connected to devices in an environment that may be subject to
voltage surges.
• To prevent electric shock, connect wires to the terminal block that match the voltage range
that you are measuring.
• Applying a voltage exceeding the value indicated below may damage the input section. If the
frequency is above 1 kHz, damage may occur even when the voltage is below this value.
Maximum input voltage (across the input terminals, H and L,
1
at a frequency of 1 kHz or less)
42 V (DC + ACpeak)
Maximum allowable common
mode voltage (across the input terminals, H or L, and earth,
2
at a frequency of 1 kHz or less)
42 V (DC + ACpeak) (CAT II, 30 Vrms)
• Wire the L input terminals for all of the sub channels on the same module to the same
potential. The L input terminals of the sub channels are all common. Because the L input
terminals are electrically connected inside the DL850/DL850V, connecting different potentials
to them could result in short circuiting and damage to the 16-CH voltage input module.
H
L
Input terminal
Ground
*2
*1
Terminal block
Wire insertion hole
H
L
Screwdriver insertion hole
Sub channel
1
2
16
The L input terminals are
electrically connected
inside the instrument
(same potential).
• When you release or lock the terminal block release levers, be careful not to injure yourself
on the levers’ protrusions.
Over-Range Indication
If over-range is indicated, the DL850/DL850V 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.
Over-range indication
Indicates the number of the channel that over-range is occurring on.
Channel indication when over-range is occurring on multiple channels
Indicates the smallest number among the channels that over-range is
occurring on.
CAUTION
When you attach the terminal block, if you try to attach it upside down, you may damage the
terminal block and the module. Check the vertical orientation of the block before you install it.
3-34
IM DL850-03EN