Hitachi electric disc grinder Grinder User Manual


 
English
10
ASSEMBLY AND OPERATION
APPLICATIONS
Removal of casting fin and finishing of various type
of steel, bronze and aluminum materials and
castings.
Grinding of welded sections or sections cut by
means of an acetylene torch.
Grinding of synthetic resins, slate, brick, marble.
WARNING:
To avoid the risk of serious injury, NEVER use this
grinder with cup wheels and/or saw blades.
PRIOR TO OPERATION
1. Power source
Ensure that the power source to be utilized
conforms to the power source requirements
specified on the product nameplate.
NOTE:
When connected to the power supply, the built-in
electronic control circuit shifts to standby status
and the grinder becomes slightly warm, but this is
not a malfunction.
CAUTION
Do not operate from a direct current power source,
engine generator, booster or any other type of
transformer. Doing so may not only cause damage
to the grinder, but may lead to accidents.
2. Power switch
Ensure that the switch is in the OFF position. If the
plug is connected to a receptacle while the switch
is in the ON position, the power tool will start
operating immediately and can cause serious injury.
When the kickback protection, 0 voltage re-start
protection or overload protection feature has been
activated, return the power switch to the OFF
position and wait for 1 second or more before re-
starting the power tool.
3. Extension cord
When the work area is far away from the power
source, use an extension cord of sufficient
thickness and rated capacity. The extension cord
should be kept as short as practicable.
WARNING:
Damaged cord must be replaced or
repaired.
4. Check the receptacle
If the receptacle only loosely accepts the plug, the
receptacle must be repaired. Contact a licensed
electrician to make appropriate repairs.
If such a faulty receptacle is used, it may cause
overheating, resulting in a serious hazard.
5. Check your work environment
Ensure the following before operation;
No flammable gas, liquid, or object at
worksite.
When grinding thin steel sheet it may cause
a high booming noise.
To avoid such noise, place a rubber mat under
the workpiece.
Clear the area of children or unauthorized
personnel.
6. Mounting the wheel guard
Be sure to mount the wheel guard at an angle that
will protect the operator’s body from injury by a
broken wheel piece.
[How to attach and adjust the wheel guard] (Fig. 2)
Set the wheel ass’y to the packing gland.
Tighten M5 screw to secure the wheel guard
while the lever is in closed position.
Perform the adjustment, of the wheel guard
while the lever is released. (Loosen M5 screw
and readjust if the wheel guard does not
rotate smoothly.)
Electronic Control
The grinder has an electronic speed control which
provides:
full speed at all times in the range up to rated load.
soft-start.
variable speed
Kickback Protection
The kickback protection feature cuts off the power
to the motor and stops the power tool in the event
of a sudden drop in the rotational speed of the
wheel during operation (for example, if the wheel
locks during cutting operation, etc.).
0 Voltage Re-start Protection
The 0 voltage restart protection feature prevents
the power tool from restarting after the power has
been temporarily cut off during operation.
Overload Protection
The overload protection feature shuts off the power
to the motor in the event of overloading of the
motor or a conspicuous reduction in rotational
speed during operation.
NOTE:
The grinder is equipped with a rotational speed
control circuit. The rotational speed may fluctuate
slightly due to the conditions of use and working
voltage.
01Eng_G12VA_US 8/3/09, 17:5110