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Operations Performed When the Power Is Turned On
When the power switch is turned on, self testing and calibration start automatically. This lasts for
approximately 30 seconds. When the DL850/DL850V starts normally, the waveform display screen
appears. Check that the DL850/DL850V has started normally before you use it.
If the DL850/DL850V Does Not Start Normally When the Power Is Turned On
Turn off the power switch, and check the following items.
• Check that the power cord is securely connected.
• Check that the correct voltage is coming to the power outlet. → Page 3-9
• Initialize the settings to their factory defaults by turning on the power switch while holding down
the RESET key. For details about initializing the settings, see section 4.6, “Initializing Settings.”
If the instrument still does not work properly, contact your nearest YOKOGAWA dealer for repairs.
Note
• After turning the power off, wait at least 10 seconds before you turn it on again.
• On the DC power supply option, repeatedly turning the power switch on and off will stop the power from
being supplied because the internal protection will be activated. If you refrain from turning the power on
or off for 10 to 20 seconds, the internal protection will be released, and power supply will be restored. The
DC power supply LED lights in orange while power is not being supplied.
• It takes several seconds for the startup screen to appear.
Operations Performed When the Power Is Turned Off
When the power switch is turned off (or the power plug is removed), the instrument stores the current
settings in its memory. This means that if you turn the power switch on and begin measurement, the
instrument will perform measurements using the settings from immediately before the instrument was
last turned off.
Note
The instrument stores the settings using an internal lithium battery. The battery lasts for approximately five
years when the ambient temperature is 23°C. When the lithium battery voltage falls below a specified value
and you turn on the power, a message (error 907) appears on the screen. If this message appears frequently,
you need to replace the battery soon. Do not try to replace the battery yourself. Contact your nearest
YOKOGAWA dealer to have the battery replaced.
To Make Accurate Measurements
• After turning on the power switch, wait at least 30 minutes to allow the instrument to warm up.
• Perform calibration after the instrument has warmed up (see section 4.7 for details). If auto
calibration is turned on, auto calibration is executed when you change the Time/div setting or start
waveform acquisition.
3.4 Connecting to a Power Supply and Turning the Power Switch On and Off
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IM DL850-03EN
Making Preparations for Measurements
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App
Index