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IM 701310-01E
Make sure to comply with the precautions below. Not complying might result in 
injury or death.
  WARNING
Use the Correct Power Supply
Before connecting the power cord, ensure that the source voltage matches the 
rated supply voltage of the DL9000 and that it is within the maximum rated voltage 
of the provided power cord.
Use the Correct Power Cord and Plug
To prevent the possibility of electric shock or fire, be sure to use the power cord 
supplied by YOKOGAWA. The main power plug must be plugged into an outlet with 
a protective earth terminal. Do not invalidate this protection by using an extension 
cord without protective earth grounding.
Connect the Protective Grounding Terminal
Make sure to connect the protective earth to prevent electric shock before turning 
ON the power. The power cord that comes with the instrument is a three-pin type 
power cord. Connect the power cord to a properly grounded three-pin outlet.
Do Not Impair the Protective Grounding
Never cut off the internal or external protective earth wire or disconnect the wiring 
of the protective earth terminal. Doing so poses a potential shock hazard.
Do Not Operate with Defective Protective Grounding or Fuse
Do not operate the instrument if the protective earth or fuse might be defective. 
Make sure to check them before operation.
Do Not Operate in an Explosive Atmosphere
Do not operate the instrument in the presence of flammable liquids or vapors. 
Operation in such environments constitutes a safety hazard.
Do Not Remove Covers
The cover should be removed by YOKOGAWA’s qualified personnel only. Opening 
the cover is dangerous, because some areas inside the instrument have high 
voltages.
Ground the Instrument before Making External Connections
Securely connect the protective grounding before connecting to the item under 
measurement or an external control unit. If you are going to touch the circuit, make 
sure to turn OFF the circuit and check that no voltage is present. To prevent the 
possibility of electric shock or an accident, connect the ground of the probe and 
input connector to the ground of the item being measured.
See below for operating environment limitations.
  CAUTION
This product is a Class A (for industrial environments) product. Operation of this 
product in a residential area may cause radio interference in which case the user 
will be required to correct the interference.
Safety Precautions