Hioki MEMORY HiCORDER 8855 Manual

GUIDE BOOK
8855
MEMORY HiCORDER

1
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Introduction
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Introduction
Thank you for purchasing the HIOKI "8855 MEMORY HiCORDER." To
obtain maximum performance from the product, please read this manual
first, and keep it handy for future reference.
About This Manual
The manual "Measurement Guide for the 8855" contains the minimum
information necessary for operation of the 8855 MEMORY HiCORDER. For
a detailed explanation of operating methods, please refer to the 8855 Quick
Start Manual and 8855 Instruction Manual. Be sure to read and understand
the sections entitled "Safety Notes" and Chapter 2 "Installation and
Preparation" in the 8855 Instruction Manuals before using the product.
Identification of Controls and Indicators 2
Operation Method of the Panel Key 3
Display Screen and Setting Screen 5
Operation flow 13
Simple measurement operations 14
Measurement of instantaneous power interruption
in a commercial power line 15
Measurement of the sensor output 21
External Memory Devices 28
Storage of measurement data 30
Reading measurement data 32
Automatic saving of measurement data 34
Real-time printing of measurement data 35
Useful Information 36

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Identification of Controls and Indicators
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1 2 93 4 5 6 7 8 10 11 12 13 14 15 16 17
1819202122
23
Right Side Panel
1Power switch Switches on or off the power supply.
2AC connector The supplied power cord must be plugged in here.
3Function ground
terminal (GND) Connects to the earth.
4External sampling
terminal Allows input of an external sampling clock. (in the Memory
function)
5Trigger terminals Can be used to synchronize multiple products, using the EXT
TRIG input and TRIG OUT output.
6PC card slot Inserts the PC card.
7Logic probe connectors Input connector for the logic input section, designed for the
dedicate logic probes (CH A to D).
8Eject button Removes the PC card.
9External output terminal Various output signals can be selected, such as the BUSY, storage,
or probe offset (1 kHz, 5 V Rectangle wave output)
10 NG evaluation output
terminal When NG results from the numerical evaluation and waveform
evaluation, a signal is output from this terminal.
11 GO evaluation output
terminal When GO results from the numerical evaluation and waveform
evaluation, a signal is output from this terminal.
12 Ground terminal (GND) Uses with 9to 14 (except 12 )terminals.
13 External stop terminals Stop operation can be controlled.
14 External start terminals Start operation can be controlled.
15 Key lock Locks the operation of keys.
Identification of Controls and Indicators

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Operation Method of the Panel Key
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16 SCSI connector An MO drive can be connected.
17 LAN connector Can be connected to a network through a LAN.
18 FD slot Floppy disk is inserted.
19 MO slot MO disk is inserted. (when the 9646 is installed)
20 Input unit slots These slots accept input units.
21 Fastening screw Secures the plug-in product.
22 Analog input connector Unbalanced analog input. (on ANALOG UNIT)
23 Blowing slot
4
5
7
1
2
13 14 19 20
3
6
8
9
10 11 12 15 16 17 18 21 22
23
24
25
26
Front Panel
Operation Method of the Panel Key

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Operation Method of the Panel Key
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1F1 to F10 key Serve to select setting items.
2HELP key Provides on-line help.
3CHAN key Causes the display to show the Channel screen which serves for making
input channel settings.
4DISP key Causes the display to show measurement and analysis results.
5FILE key Causes the display to show the File screen which serves for reading, storing,
etc. the waveform data etc.
6TRIG key Causes the display to show the Trigger screen. Setting the trigger functions.
7STATUS key Causes the display to show the Status screen which serves for setting most
measurement parameters.
8TIME/DIV key Serves to set the speed for inputting and storing the input signal.
9SYSTEM key Causes the display to show the System screen. Makes all the settings of
common functions, such as the initial settings and various other settings.
10 PRINT key Serves to print out stored waveforms.
11 COPY key Serves to print out a hard copy of the current screen display.
12 FEED key Causes the printer paper to advance for as long as the key is pressed.
13 CURSOR key These keys serve to move the flashing cursor in the four directions.
14 SAVE key Saves the data on the specified media.
15 AUTO key Pressing this key activates automatic setting of time axis range and voltage
range values of input waveform.
16 VALUE key Uses to select the numerical values setting.
17 WAVE key Uses to select the the waveform scrolling.
18 JOG Rotary control knob that serves to change values, move the A/B cursors,
and scroll the waveform.
19 SHUTTLE Concentric ring that serves to change values, move the A/B cursors, and to
scroll the waveform. The speed of movement is proportional to the rotation
angle.
20 A.B CSR key Uses to select the the A/B cursor moving.
21 RANGE knob Sets the measurement range for the channel.
22 STOP key Stops measurement and analysis.
Pressing this key twice stops measurement.
23 START key Initiates the measurement and analysis. During measurement, the LED
above the key is lit.
24 POSITION knob Sets the zero position for the channel.
25 Channel select
keys Selects channel.
26 ESC key Exits the Input or Set up screen.

5
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Display Screen and Setting Screen
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Waveform display screen
The screen shown below appears immediately after the power switch is turned on. The waveform
display screen can also be displayed by pressing the red DISP key. The following explains the
displayed items and the items that can be set in the waveform display screen.
Indicates the measurement
function
(Memory/Recorder/R&M/FFT)
When the flashing cursor is
located here, the function
key can be used to switch
functions.
Indicates the time axis (horizontal axis)
and sampling frequency
The screen shows the time (/DIV)
per DIV (grid) and the sampling time
(/S). The function key or TIME/DIV
knob is used to switch the display.
Indicates the trigger
mode (single / repeat
/ auto)
The function key is
used to switch the
mode.
Indicates pre-trigger
Used to set the
percentage of the pre-
trigger waveform to be
acquired in the total
recording length.
Indicates the recording length
and recording time
Used to set the length
(time) to be recorded in a
single acquisition
operation. The function key
is used to change the
setting.
Indicates the displayed
channel.
Indicates time-axis
zoom (horizontal
axis)
A waveform can be
magnified or
compressed along
the time axis. The
function key is
used to change the
zoom rate.
Indicates the trigger
activation point.
Indicates the elapsed time
from the trigger.
Indicates the current
date and time.
Indicates operation
settings other than
those for waveform
loading
From the left, the
icons indicate the
following settings:
Calculation
Auto print
Auto save
CH setting key
Other settings can be made by pressing the CH setting key ( F9 function key) in the waveform
display screen. Each time the F9 key is pressed, the CH setting screen changes as shown on
the next page, and displays channel information or allows setting to be performed.
CH setting screen
F9
Display Screen and Setting Screen

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Display Screen and Setting Screen
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CH setting
F9
Input unit setting
The following settings can
be entered for each
channel:
Display ON/OFF
Voltage axis range
(vertical axis) setting
Zero-position setting
Display graph setting
Coupling setting
Magnification /
compression of the
vertical axis
Low-path-filter setting
Trigger setting
The following settings can
be entered for each
channel.
(Analog only)
Display ON/OFF
Trigger type setting
Trigger level setting
Trigger slope setting
For the setting of other
items, use the trigger
screen.
Comment display
Comments for each channel
can be displayed.
Comments cannot be input
in the waveform display
screen. To enter a
comment, press the CHAN
key to display the comment
setting screen.
Logic waveform display
Display settings for each
logic waveform can be
adjusted. The following
settings can be entered on
this screen:
Logic display ON/OFF
Display position
CH setting
F9
CH setting
F9
OFF
CH setting
F9
Back to the input
unit setting screen.
CH setting
F9

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Display Screen and Setting Screen
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Channel screen
The channel screen can be displayed by pressing the CHAN key located on the left side of the
unit. This screen is used to set units (analog input) and to enter logic input, display the settings
for each channel, and to enter scaling settings, comments, and other detail settings.
The above screen shows the analog-setting list page. Press the Page Switch key ( F3 function
key) to change the display to pages for logic input setting, X-Y setting, and details (options)
setting. The following describes each of these pages.
Page change key
List
Indicates the channel. Settings can be copied between channels.
Indicates the unit type.
Used to select waveform display ON/OFF.
Used to select waveform graph ON/OFF.
This item is enabled when the display shows multiple screens.
Used to select the measurement mode. (voltage, current,
temperature, etc.)
Used to select the vertical axis (voltage axis) range.
Used to select the input coupling setting. (AC, DC, GND)
Used to select the low path filter ON/OFF.
Used to select vertical axis (voltage axis) zoom.
Used to set the zero position . This allows selection of the zero-
level setting point in the screen.
Used to select variable ON/OFF. The position and size of the
displayed waveform can be changed.
Indicates the voltage value per DIV (grid).
This setting can be entered when Variable is ON.
Indicates the upper- and lower-limit values of the display screen.
This setting can be entered when Variable is ON.
Indicates the upper- and lower-limit values within the selected
measurement range. Measurement cannot exceed these levels.
Indicates the measurement unit of the vertical axis.
Logic page
Selection of logic
waveform display
ON/OFF, display position,
display width, and analog
input waveform resolution
display ON/OFF (For
details, refer to section
6.3.10 of the Quick Start
Manual.)
Page
F3
XY page
This screen is enabled
when the display mode
(setting item in the status
screen) is set to "XY
screen."
XY waveform setting
(ON/OFF) and channel
selection for the X- and
Y-axes
Page
F3

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Display Screen and Setting Screen
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In addition to the list page shown on the previous page, the channel screen includes the three
types of pages specified below. To change pages, press the menu key ( F1 F2 function keys)
or CHAN key.
Options page
Selection of the probe pressure-
distribution ratio when the 9665, 9666,
or 9322 is used
Setting of the antialiasing filter (enabled
when used with the 8953-10 unit)
Setting of details (reference contact,
burnout) for temperature measurement
when used with the 8954 unit
Setting of details (threshold, hold, level,
etc.) when used with the 8955 unit
ONE CH
These pages are used to enter settings for individual
channels. Since the page displays a level monitor and
numerical values, variable and scaling settings can be
entered while the input level is monitored.
SCALING
This page is used to enter scaling settings. It allows the
setting of scaling values for all channels. For details, refer to
5.3 "Scaling Function" in the Instruction Manual.
COMMENT
This page is used to enter comments. It allows the input of
comments for all channels (logic). For details, refer to 5.4
"Comment Function" in the Instruction Manual.

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Display Screen and Setting Screen
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Trigger screen
The trigger screen can be displayed by pressing the TRIG key located on the left side of the
unit.
This screen is used to set the trigger for each channel.
To switch the page between analog and logic, press the Page Switch key ( F3 function key).
Analog trigger setting
Trigger acceptance setting (single / repeat /
auto)
When set to "Single," one trigger is
accepted. When set to "Repeat," a trigger
is accepted even after completion of data
acquisition. In "Auto," data is obtained
after a certain time period even without
trigger activation.
Pre-trigger setting (waveform prior to
trigger activation)
Used to set the percentage of pre-
trigger waveform in the total
recording length.
When "Priority on trigger" is turned
ON, a trigger is accepted even in
pre-trigger waiting mode.
Trigger source setting
(AND/OR)
A trigger can be activated
based on AND/OR
conditions among the analog
trigger, logic trigger, external
trigger, and timer trigger.
Timer trigger setting
A trigger can be activated at
set intervals between the
start time and stop time.
External trigger setting
A trigger can be activated by
an input signal from an
external trigger terminal
(EXT.TRIGterminal).
Trigger filter setting
A trigger is activated when
the trigger condition is met
for the filter width set using
this item. It prevents trigger
activation by noise.
Trigger kind setting
The trigger type can be
selected from among the
level trigger, window
trigger, frequency trigger,
glitch trigger, and event
trigger.
Trigger level setting
A trigger is activated
when an input signal
crosses the trigger level
set using this item.
Trigger slope setting
A trigger is activated
when an input signal
complies with the trigger
slope (rising edge, falling
edge) set using this item.
Logic trigger setting
Logic trigger filter setting
A trigger is activated
when the trigger
condition is met for the
filter width set using this
item. It prevents trigger
activation by noise.
Logic trigger pattern setting
A logic input-signal
trigger pattern can be set
for each probe.
Logic trigger AND/OR
setting
The trigger AND/OR
condition can be set for
each logic probe.

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Display Screen and Setting Screen
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Status screen
The status screen can be displayed by pressing the STATUS key located on the left side of the
unit. This screen is used to enter basic waveform data-acquisition settings, memory allocation
settings, and calculation settings.
In addition to the basic setting page shown above, the status screen includes the three pages
specified below. To change pages, press the menu key ( F1 F2 function keys) or CHAN key.
Regarding the setting method, refer to the Instruction Manual provided with the product.
STATUS Used to set the time axis (horizontal axis). The sampling speed
changes automatically.
Used to set recording length. The recording time changes
automatically.
The recording length can be set in increments of 1 DIV.
Used to set the number of screens for split display
The display mode can be selected from among four types: 1-
screen, 2-screen, 4-screen, 8-screen, and X-Y1 screen.
When roll mode is set, the screen changes (scrolls) in sync with
waveform recording at time axis slower than 10 ms/DIV.
The waveform judgment function can be
used when this is turned ON. For details,
refer to Chapter 9 "Waveform Evaluation
Function" in the Instruction Manual.
When "Superimposition" is turned ON, a new waveform is
displayed over the previous waveform if the trigger mode is set
to "Repeat" or "Auto."
When "Averaging" is turned ON, waveform data is obtained the
set number of times, and the average of all data is displayed.
The "Channel in use" item is used to set the number of channels
for measurement-data memory allocation.
MEMORY DIV (Chapter 6 "Memory
Segmentation Function" in the Instruction Manual)
MEASUREMENT (Chapter 7: 7.1
"Numerical Calculation" in the Instruction Manual)
WAVE CULC (Chapter 7: 7.2
"Waveform Calculation" in the Instruction Manual)

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Display Screen and Setting Screen
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System screen
The system screen can be displayed by pressing the SYSTEM key located on the left side of the
unit.
To change pages, press the menu key ( F1 F2 function keys).
The system screen is used to enter settings common to all functions; settings for printer, files,
and communication; 8855 initial settings; and self-diagnosis settings.
The following briefly describes each of these setting pages.
SET UP (Refer to 9.2 "Set Up Screen" in the Quick Start
Manual.)
Display settings (grid display, comment display, etc.)
Start condition settings (start backup, etc.)
External control terminal settings (GO. NG terminal, probe
correction output setting)
SCSI settings (ID setting, external MO setting, PC
connection setting)
FILE SAVE (Refer to 9.3 "File Screen" in the Quick Start
Manual.)
Auto-save settings (destination, file save format, saving
range, etc.)
Storage of numerical processing results (destination,
saving method)
SAVE key setting (saving operation performed when the
SAVE key is pressed)
PRINTER (Refer to 9.4 "Printer Screen" in the Quick Start
Manual.)
Printer settings (Grid, density, gauge, marker, size, etc.)
Printing format settings
Comment printing settings
Printing destination setting (printer, LAN equipment)
Real-time print settings (recorder function, R&M)

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Display Screen and Setting Screen
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INTERFACE (Refer to Chapter 11 "Communication
Settings" in the Instruction Manual.)
LAN settings
FTP settings
PC card settings (RS-232C, GP-IB, modem)
PPP settings (transmission, reception, etc.)
INITIALIZE (Refer to 9.5 "Initialize Screen" in the Quick
Start Manual.)
Clock setting
Waveform data initialization
System reset
Menu control (display/hide setting)
SELF CHECK (Refer to 9.6 "Self-check" in the Quick Start
Manual.)
ROM/RAM check
Printer check
Display check
Key check
System component list (option information, version
information, etc.)

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Measurement Method
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Operation flow
1
What is the measurement target
object?
What is the voltage of the target
object?
Check the maximum input voltage.
Check the maximum ground input voltage.
2Connect the power cord to the
8855 unit.
Confirm that the power-supply voltage is 100 VAC to 200 VAC.
Confirm that the power-supply frequency is 50/60 Hz (sine
wave).
3Connect to the measurement
target object.
Confirm that the power switch of the measurement target object
is turned off.
4Turn on the power switch.
Turn on the power switch located
on the right side of the unit.
5Select a measurement function.
In each screen, move the flashing cursor to the top (upper left)
item.
There are four selectable items: memory, recorder, R&M, and
FFT.
6Set the time axis.
Press the DISP or STATUS key.
Make settings in the display or status screen.
Sampling frequency (s) = Time axis (s/DIV) / 100 (number of
pieces of data per DIV)
7Set the recording length.
Press the DISP or STATUS key.
Make settings in the display or status screen.
Measurement times (s) = Time axis (s/DIV) / recording length
(DIV)
8Set the input channel.
Press the CHAN key.
Make settings in the channel screen.
Voltage axis range, zero position, coupling, filter, etc.
9Make trigger settings.
Press the TRIG key.
Make settings in the trigger screen.
Trigger mode, pre-trigger, trigger type, trigger level, etc.
10 Begin measurement.
Press the START key.
On the front panel of the main unit, press the green START
key located at the lower right corner.
The LED lights up, and measurement starts.
11 End measurement.
Press the STOP key.
(Trigger mode: Continuous/Auto)
In the single-trigger mode, measurement ends when data of the
set recording length is obtained. In the continuous or auto
trigger mode, measurement ends when the STOP key is
pressed. To abort measurement, press the STOP key twice.
12 Begin analysis.
Waveform zoom (Refer to Chapter 8 in the 8855 Quick Start Manual.)
A-B cursors (Refer to Chapter 8 in the 8855 Quick Start Manual.)
Numerical processing, waveform processing (Refer to Chapter 7 in the
8855 Instruction Manual.)
Waveform search (Refer to Chapter 8 in the 8855 Instruction Manual.)
Measurement Method
Pre-measurement operations
Setting up the main unit
Starting measurement
Starting analysis

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Measurement Method
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Simple measurement operations
The following describes the simple operating procedures with a waveform input into Channel 1
(CH1) of the 8855 HiCORDER.
(Example) Input of a sine wave of 1 kHz and 1 V, and observation of the waveform
(1) Press the DISP key to display the waveform
display screen.
(2) Move the flashing cursor to the "Function" indication
at the upper left corner of the screen, then press
the F1 key and select "Memory."
(3) Press the CH1 button key of the CH. SELECT
key.
(4) Turn the RANGE knob to set the voltage axis
range to "200 mV/DIV."
(5) Turn the POSITION knob to set the zero position
to "50%."
The above settings set the full scale (upper- and
lower-limit values) on the display to " 2V."
(6) Turn the TIME/DIV knob to set the time axis to
"100 µs/DIV."
(7) Move the flashing cursor to "Trig" in the screen,
and press the F3 key to set to "AUTO."
Regarding the trigger setting method, refer to the
"Trigger screen" section of this manual or Chapter 7
"Trigger Functions" in the Quick Start Manual.
The settings for waveform observation have been
entered in the above steps.
(8) Start measurement. Press the START key located
at the lower right corner of the front panel. The
green LED located next to the START key remains
lit while waveform data is being acquired.
(9) To abort the measurement, press the STOP key
l o c a t e d n e x t t o t h e START key. When the
measurement is aborted, the green LED next to the
START key turns off.
< Key point >
The voltage axis range, position, and time axis
range can be changed during a starting operation.
To make changes, use the RANGE ,
POSITION , and TIME/DIV knobs.
Procedure

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Measurement Method
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Measurement of instantaneous power interruption in a
commercial power line
DANGER To prevent electric shock and equipment damage, make sure
each unit's maximum input voltage and maximum rated
ground voltage (described in Chapter 2 "Installation and
Preparation" in the Instruction Manual provided with the
product) are not exceeded.
Use the 8950 ANALOG UNIT to measure instantaneous power interruption in a commercial 100-
V power supply (50 Hz). The 8951 VOLTAGE/CURRENT UNIT and 3273 CLAMP ON PROBE
are also used at the same time to measure the amount of current flowing to equipment.
CH1: Connection of the 9198 to the 8950 ANALOG UNIT
Connect the cord and measure the commercial power supply.
CH2: Connection of the 9198 to the 8950 ANALOG UNIT
Connect the cord and measure the internal voltage of equipment likely to be affected by
instantaneous power interruption.
CH3: Connect the 3273 CLAMP ON PROBE to the 8951 VOLTAGE/CURRENT UNIT, and measure the
current flowing in the equipment during instantaneous power interruption.
2. Connection
1. Method
Equipment
5V
12 V
GND
100 V
50 Hz
3273
9198
CH1
CH2
CH3
8855
9198

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Measurement Method
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4. Details
1. Setting the time axis and recording length
For the observation of waveforms before and
after an instantaneous power outage, follow the
setting procedure described below.
Press the STATUS key to display the status
screen.
Move the flashing cursor to "Time/Div" or
"Shot."
Since the frequency of the commercial power
supply to be measured is 50 Hz (20 ms), use
the functions to set the "Time/Div" to "20
ms/DIV," and the "Shot" to "30 DIV."
3. Setup
Display Setting item Setting
Status screen Time axis (Time/Div) 20 ms/DIV
Recording length (Shot) 30DIV
Display mode (Format) Dual
Channel screen Graph CH1 GR1
CH2 GR2
CH3 GR2
Mode CH1 Voltage
CH2 Voltage
CH3 3273
Range CH1 20 V
CH2 2V
CH3 1A
Trigger screen Trigger mode Single
Pre-trigger 20%
Kind CH1 In
Parameter CH1 Lower (limit): -100.00 V
Upper (limit): 100.00 V
Filt. (Filter): 1.5 DIV
Display the status screen.
Move to "Time/Div" or
"Shot."
Press the function key corresponding to the setting
displayed in the screen.
Status screen
Set to 20 ms/DIV.
Set to 30 DIV.

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Measurement Method
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2. Window display
(1) Separate the display of commercial power-supply
waveforms from the display of other waveforms to
prevent overlapping.
Using the cursor keys, move the flashing cursor to
"Format." Then, press the function key to set the
"Format" to "DUAL."
(2) Press the CHAN key to display the channel
screen.
Move the flashing cursor to "Graph," and set Graph
CH1 to "GR1," and CH2 and CH3 to "GR2."
Move to "Format."
Press the function key corresponding to the setting
displayed in the screen.
Move to "Graph."
Press the function key corresponding to the setting
displayed in the screen.
Set to DUAL.
Channel screen
Status screen
Set to GR1 or GR2.
Display the channel screen.

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Measurement Method
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3. Channel setting
Using the cursor keys, move the flashing cursor
to "Range" or "Mode."
Since CH1 receives a commercial 100-V power
supply (approx. 141 Vp), press the function key
to set the range (vertical axis) to "20 V/DIV."
Since CH2 is used to observe the interval
voltage (12 VDC) of the equipment, press the
function key to set the range (vertical axis) to
"2V/DIV
."
CH3 measures the amount of current. Press the
function key to set the mode to "3273." Although
the current flowing in the equipment is normally
1A, it can increase to 10 times that level at the
time the power switch is turned on. Therefore,
press the function key and set the range
(vertical axis) to "1A/DIV
."
< Key point >
When ranges are set in the channel screen, the
displayed upper- and lower-limit values and the
upper- and lower-limit values for measurement
vary according to the entered ranges. Refer to
these limit values when setting the ranges.
Move to "Range" or "Mode."
Press the function key corresponding to the setting
displayed in the screen.
Set to 3273.
Channel screen
Set each range.
These settings
change according
to the range.

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Measurement Method
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4. Trigger setting
The following describes the trigger condition
setting method.
To activate the trigger at the time of
instantaneous power outage, use "Window In
trigger."
A commercial 100 V power supply has a sine
waveform that ranges from -141 V to 141 V.
In the following setting, the lower limit of the
Window In trigger is set to "-100 V" and the
upper limit to "100 V," and the trigger is
activated when the waveform enters the shaded
range (window) in the left diagram. This setting
activates the trigger every time the waveform
enters the window. Therefore, a time duration
(trigger filter) is set so that the trigger is
activated only when the waveform remains in
the window for longer than the set time.
The frequency of a commercial power supply is
50 Hz, meaning that one cycle is 20 ms.
Instantaneous power outage is a condition in
which the voltage drops for a period longer than
20 ms. Therefore, the trigger filter is used to set
a period in units of DIV. Since the time axis is
set to 20 ms/DIV, the trigger filter is set to be
longer than 20 ms. In the example, the trigger
filter is set to "1.5 DIV." With this setting, the
trigger is activated when waveform remains in
the window for 30 ms or longer.
(1) Press the TRIG key to display the trigger screen.
(2) Using the cursor keys, move the flashing cursor to
CH1 "Kind," and press the function key to change
the type to "In."
(3) Move the flashing cursor to CH1 "Parameter," and
set the lower (limit) to "-100.00 V," the upper (limit)
to "100.00 V," and the filter (Filt.) to "1.5 DIV."
(4) Move the flashing cursor to "Trigger mode," and set
the trigger mode to "Single" (stops after
instantaneous power outage occurs and a
waveform is acquired).
(5) Move the flashing cursor to "Pre-trigger," and set
the pre-trigger to "20%" (for observation of
waveforms prior to the trigger).
< Key point >
By combining the Window In trigger
upper- and lower-limit values with
the filter, it is possible to detect not
only a trigger caused by an
instantaneous power outage but also
waveform chipping and voltage dips
in repeated waveforms.
Move to "Type," "Parameter,"
"Trigger mode," and "Pre-trigger."
Press the function key corresponding to the setting
displayed in the screen.
Trigger screen
Set to "In," "-100.00 V," "100.00 V,"
and "1.5 DIV."
Display the trigger screen.
Set to "Single" and "20%."