Panasonic Ey4640 Operating Instructions Manual

							- 11  -  
charger and battery pack with a 
cloth, etc., while charging.
 22) Use of an attachment not recom-
mended may result in a risk of fire, 
electric shock, or injury to persons.
 23) Do not short the battery pack. A 
battery short can cause a large cur-
rent flow, over heating and burns.
  24)  NOTE: If the supply cord of this ap-
pliance is damaged, it must only be 
replaced by a repair shop appoint-
ed by the manufacturer, because 
special purpose tools are required.
 25) 
TO REDUCE THE RISK OF ELEC-
TRIC SHOCK, THIS APPLIANCE HAS 
A POLARIZED PLUG (ONE BLADE IS 
WIDER THAN THE OTHER).
  This plug will fit in a polarized outlet 
only one way. If the plug does not fit 
fully in the outlet, reverse the plug. If 
it still does not fit, contact a qualified 
electrician to install the proper outlet. 
Do not change the plug in any way.
 
WARNING:
• Do not use other than the Panason-
ic battery packs that are designed 
for use with this rechargeable tool.
• Do not dispose of the battery pack in 
a fire, or expose it to excessive heat.
• Do not drive the likes of nails into the 
battery pack, subject it to shocks, 
dismantle it, or attempt to modify it.
• Do not allow metal objects to touch 
the battery pack terminals.
• Do not carry or store the battery 
pack in the same container as nails 
or similar metal objects.
• Do not charge the battery pack in 
a high-temperature location, such 
as next to a fire or in direct sunlight.  
Otherwise, the battery may over-
heat, catch fire, or explode.
• Never use other than the dedicated 
charger to charge the battery pack.  
Otherwise, the battery may leak, 
overheat, or explode.
• After removing the battery pack 
from the tool or the charger, always 
reattach the pack cover.  Otherwise, 
the battery contacts could be short-
ed, leading to a risk of fire.
IV. ASSEMBLY
NOTE:When attaching or removing a slide han-
dle, disconnect battery pack from tool.
  
CAUTION:
• Always be sure that the side han-
dle is installed securely before op-
eration.
Screw the side handle securely as 
shown in the figure.
  CAUTION:
• Never actuate the lock pin when 
the spindle is rotating. The tool 
may be damaged.
Press the lock button to prevent spindle 
rotation when installing or removing parts, 
such as grinding disc, disc guard, etc.
Installing or removing disc
Inspection before use•  Has the correct grinding disc been 
mounted for the object to be ground?
•  Has the proper diameter of the grind-
ing disc been mounted for the tool 
rating?
•  Has the proper grinding disc com-
plied to safety standard listed below 
been mounted?
  U.S.A, Canada - ANSI
1. Grinding disc 
guard
2. Spindle
3. Grinding disc 
guard fixing
 screw
3
2 1 
						

							- 12 -   
 CAUTION:
• When using, the Grinding disc 
guard must be installed on the 
tool so that the closed side of the 
guard always faces toward the op-
erator.
• Ensure that blotters are used 
when they are provided with the 
bonded abrasive product and 
when they are required;
   WARNING:
• Always use supplied guard when 
using tool. Grinding disc can shat-
ter during use and Grinding disc 
guard helps to reduce chances of 
personal injury.
1. Install the Grinding disc guard, and 
then securely tighten the screw.
1. Clamp nut
2. Grinding
disc
3. Disc flange
2 1
3
2.  Install the disc flange and the disc to the 
spindle in order as shown in the figure.
3. Tighten the clamp nut onto the spin-
dle so that hollow side faces oppo-
site direction to the disc.
4. Push the Spindle lock button to se-
cure the spindle in place, and then 
use the clamp nut wrench to tighten 
the clamp nut securely.
1. Spindle lock 
button
1
5. To remove the grinding disc, follow 
the installation procedure in reverse.
Attaching or Removing Battery 
Pack
1.  To connect the battery pack:
Line up the alignment marks and at-
tach the battery pack.
• Slide the battery pack until it locks 
into position.
Alignment marks
2.  To remove the battery pack:
Push on the button from the front to 
release the battery pack.
Button
V. OPERATION
NOTE:Be aware that this tool is always in 
an operating condition, since it does 
not have to be plugged into an elec-
trical outlet.
Power switch operation
1. Power switch1
  CAUTION:
• Before inserting the battery pack 
into the tool, always make sure 
that the power switch operates  
position when the rear of the pow-
er switch is depressed.
• Power switch can be locked in 
“ON” position. Stay alert when 
locking tool in “ON” position and 
grasp the tool firmly using sup-
port handle and grip.
Make sure 
the side. 
						

							- 13 -  
To start the tool, press and slide the 
power switch toward the “ON” posi-tion. 
For continuous operation, press the 
front of the power switch to lock it.
To stop the tool, press the rear of the 
power switch, then slide it toward the 
“OFF” position.
  
WARNING:
• It should never be necessary to 
force the tool. The weight of the 
tool applies adequate pressure. 
Forcing and excessive pressure 
could cause dangerous grinding 
disc breakage.
• ALWAYS replace grinding disc if 
tool is dropped while grinding.
• NEVER bang or hit grinding disc.
• Avoid bouncing and snagging the 
grinding disc, especially when 
working corners, sharp edges etc. 
This can cause loss of control and 
kickback.
  CAUTION:
• After operation, always switch off 
the tool and wait until the wheel 
has come to a complete stop be-
fore putting the tool down.
Visual inspection and workout 
test on disc
1.  Always make sure that the disc has 
no cracks before use.
2.  Always give workout test on the 
blade as follows.
3.  Always make sure the disc is firmly 
fixed.
      Work out time
Brand new disc more than 3 min.
Before use on 
current discmore than 1 min.
Grinding operation
A B
ALWAYS hold the tool firmly with one 
hand on grip and the other on the side 
handle. Turn on the tool on and then ap-
ply the wheel or disc to the workpiece.
In general, keep the edge of the wheel 
or grinding disc at an angle of about 15 
degrees to the workpiece surface.
When using a new grinding disc, do not 
work the grinder in the B direction or it will 
cut into the workpiece. Once the edge of 
the grinding disc has been rounded off by 
use, the grinding disc may be worked in 
both A and B direction. 
						

							- 14 - 
Using a cut-off disc guard 
(EY9X213E) (Available as an 
accessory, not included)
Make sure the side.
  
WARNING:
• When using an abrasive cut-off 
disc, be sure to use only the cut-
off disc guard designed for this 
use with cut-off disc.
• NEVER use cut-off disc for grinding.
• Do not jam the Disc or apply ex-
cessive pressure. Do not attempt 
to make an excessive depth of 
cut. Overstressing the cut-off disc 
increases the loading and suscep-
tibility to twisting or binding of the 
cut-off disc in the cut and the pos-
sibility of kickback, cut-off disc 
breakage and overheating of the 
motor may occur.
• Do not start when disc is in the 
workpiece. To do so causes the cut-
off disc binding or kickback. Let the 
cut-off disc reach full speed and 
then carefully cut the workpiece.
• During cutting operations, never 
change the angle of the disc. Plac-
ing side pressure on the cut-off 
disc (as in grinding) will cause the 
disc to crack and break, causing 
serious personal injury.
  CAUTION:
• To prevent excessive temperature 
increase of the tool surface, do 
not operate the tool continuously 
using two or more battery packs. 
The tool needs cool-off time be-
fore switching to another pack.
• Do not close up ventilation slots 
on the sides of the body during 
operation. Otherwise, the machine 
function is adversely affected to 
cause a failure.
• Do NOT strain the tool (motor). 
This may cause damage to the unit.• Use the tool in such a way as to 
prevent the air from the ventila-
tion slots from blowing directly 
onto your skin. Otherwise, you 
may get burned.
Indicator lamp for On lock 
warning lamp function
The grinder will not start when the 
switch is at the ON position (switch le-
ver at ON), even when the battery pack 
is inserted. The warning lamp will flash 
at this time to indicate that the on lock 
start prevention function has operated.
Press the switch to the OFF position 
(switch lever at OFF) and then press it 
back to the ON position (switch lever at 
ON) to start the grinder.
ON OFF 
						

							- 15 -  
Overheat warning lamp
Off 
(normal 
operation)Flashing: Overheat
Indicates operation 
has been halted due to 
battery overheating.
The overheating protection feature halts 
operation to protect the battery pack 
in the event of overheating. The over-
heat warning lamp on the control panel 
flashes when this feature is active.
• If the overheating protection feature 
activates, allow the tool to cool thor-
oughly (at least 30 minutes). The 
battery is ready for use when the 
over-heat warning lamp goes out.
• Avoid using the tool in a way that 
causes the overheating protection 
feature to activate repeatedly.
Battery low warning lamp
Off 
(normal 
operation)Flashing
(No charge)
Battery protection 
feature active
Excessive (complete) discharging of 
lithium ion batteries shortens their ser-
vice life dramatically. The tool includes 
a battery protection feature designed 
to prevent excessive discharging of the 
battery pack.
• The battery protection feature acti-
vates immediately before the battery 
loses its charge, causing the battery 
low warning lamp to flash.
• If you notice the battery low warn-
ing lamp flashing, charge the battery 
pack immediately.- Accidental re-start preventive function
-  Even if the battery pack is inserted on 
the tool with the power switch in the 
“ON” position, the tool does not start. 
At this time, the lamp flickers slowly 
and this shows that the accidental re-
start preventive function is at work.
-  To start the tool, first slide the power 
switch toward the “OFF” position and 
then slide it toward the “ON” position.
[Battery Pack][Battery Pack]
For Appropriate Use of For Appropriate Use of 
Battery packBattery pack
Li-ion Battery pack (EY9L40)
•  For optimum battery life, store the Li-
ion battery pack following use with-
out charging it.
• When charging the battery pack, 
confirm that the terminals on the bat-
tery charger are free of foreign sub-
stances such as dust and water etc. 
Clean the terminals before charging 
the battery pack if any foreign sub-
stances are found on the terminals.
  The life of the battery pack termi-
nals may be affected by foreign sub-
stances such as dust and water etc. 
during operation.
• When battery pack is not in use, 
keep it away from other metal ob-
jects like: paper clips, coins, keys, 
nails, screws, or other small metal 
objects that can make a connection 
from one terminal to another.
  Shorting the battery terminals togeth-
er may cause sparks, burns or a fire.
• When operating the battery pack, 
make sure the work place is well 
ventilated.
• When the battery pack is removed 
from the main body of the tool, re-
place the battery pack cover imme-
diately in order to prevent dust or dirt 
from contaminating the battery ter-
minals and causing a short circuit. 
						

							- 16 - 
Battery Pack Life
The rechargeable batteries have a lim-
ited life. If the operation time becomes 
extremely short after recharging, re-
place the battery pack with a new one.
Battery Recycling
ATTENTION:
FOR Li-ion Battery Pack, EY9L40
A Li-ion battery that is recyclable pow-
ers the product you have purchased. 
Please call 1-800-8-BATTERY for infor-
mation on how to recycle this battery.
[Battery Charger][Battery Charger]
ChargingCharging
Cautions for the Li-ion Battery 
Pack
•  If the temperature of the battery pack 
falls approximately below −10°C 
(14°F), charging will automatically 
stop to prevent degradation of the 
battery.
Common Cautions for the Li-
ion/Ni-MH/Ni-Cd Battery Pack
• The ambient temperature range 
is between 0°C (32°F) and 40°C 
(104°F).
  If the battery pack is used when the 
battery temperature is below 0°C 
(32°F), the tool may fail to function 
properly.
• When charging a cool battery pack 
(below 0°C (32°F)) in a warm place, 
leave the battery pack at the place 
and wait for more than one hour to 
warm up the battery to the level of 
the ambient temperature.
•  Cool down the charger when charg-
ing more than two battery packs con-
secutively.
• During charging, the charger may 
become slightly warm. This is nor-
mal. Do NOT charge the battery for 
a long period.
  CAUTION:
To prevent the risk of fire or damage to 
the battery charger.
• Do not use power source from an 
engine generator.
• Do not cover vent holes on the 
charger and the battery pack.
• Unplug the charger when not in use.
Li-ion Battery Pack
NOTE:
Your battery pack is not fully charged 
at the time of purchase. Be sure to 
charge the battery before use.
Battery charger (EY0L80)
1. Plug the charger into the AC outlet.
NOTE:
Sparks may be produced when the 
plug is inserted into the AC power 
supply, but this is not a problem in 
terms of safety.
2. Insert the battery pack firmly into the 
charger.
1. Line up the alignment marks and 
place the battery onto the dock on 
the charger.
2. Slide forward in the direction of the 
arrow.
Alignment 
marks
3. During charging, the charging lamp will 
be lit.
When charging is completed, an inter-
nal electronic switch will automatically 
be triggered to prevent overcharging.
• Charging will not start if the battery 
pack is warm (for example, immedi-
ately after heavy-duty operation).
The orange standby lamp will be 
flashing until the battery cools down.
Charging will then begin automatically.
 4. The charge lamp (green) will flash 
slowly once the battery is approximate-
ly 80% charged. 
						

							- 17 -  
5. When charging is completed, the 
charging lamp will start flashing quickly 
in green color.
6. If the temperature of the battery pack 
is 0°C or less, charging takes longer to 
fully charge the battery pack than the 
standard charging time.
Even when the battery is fully charged, 
it will have approximately 50% of the 
power of a fully charged battery at nor-
mal operating temperature.7. If the power lamp does not light im-
mediately after the charger is plugged 
in, or if after the standard charging 
time the charging lamp does not flash 
quickly in green, consult an authorized 
service center.
8. If a fully charged battery pack is insert-
ed into the charger again, the charging 
lamp lights up. After several minutes, 
the charging lamp may flash quickly to 
indicate the charging is completed.
Ni-MH/Ni-Cd Battery Pack
NOTE:
When you charge the battery pack for the first time, or after prolonged storage, 
charge it for about 24 hours to bring the battery up to full capacity.
Battery charger (EY0L80)
1. Plug the charger into the AC outlet.
NOTE:
Sparks may be produced when the plug is inserted into the AC power supply, but 
this is not a problem in terms of safety.
2. Insert the battery pack firmly into the charger.
3. During charging, the charging lamp will be lit.
When charging is completed, an internal electronic switch will automatically be trig-
gered to prevent overcharging.
•  Charging will not start if the battery pack is warm (for example, immedi-ately af-
ter heavy-duty operation).
The orange standby lamp will be flashing until the battery cools down. Charging 
will then begin automatically.
4. When charging is completed, the charging lamp will start flashing quickly in green 
color.
5. If the charging lamp does not light immediately after the charger is plugged in, or if 
after the standard charging time the charging lamp does not flash quickly in green, 
consult an authorized service center.
6. If a fully charged battery pack is inserted into the charger again, the charging lamp 
lights up. After several minutes, the charging lamp may flash quickly to indicate the 
charging is completed. 
						

							- 18 - 
LAMP INDICATIONSLAMP INDICATIONS
Green Lit
Charger is plugged into the AC outlet.
Ready to charge.
Green Flashing Quickly
Charging is completed. (Full charge.)
Green Flashing
Battery is approximately 80% charg ed. (Usable charge. Li-
ion only)
Green Lit
Now charging.
Orange Lit
Battery pack is cool.
The battery pack is being charged slowly to reduce the load 
on the battery. (Li-ion only)
Orange Flashing
Battery pack is warm. Charging will begin when temperature 
of battery pack drops.
If the temperature of the battery pack is –10°C or less, the 
charging status lamp (orange) will also start fl ashing.  Charging 
will begin when the temperature of the battery pack goes up (Li-
ion only)
Charging Status Lamp
Left: green Right: orange will be displayed.
Both Orange and Green Flashing Quickly
Charging is not possible. Clogged with dust or malfunction of 
the battery pack. 
						

							
- 19 -  
Replacing carbon brushes
Keep the carbon brushes clean and 
free to slip in the holders. When it is 
less than 5 mm (3/16”) shorter both 
carbon brushes should be replaced at 
the same time. Use only identical car-
bon brushes.
Insert the top end of slotted bit screw-
driver into the notch in the tool and re-
move the brush cap cover by lifting it 
up.
1. Brush cap 
cover
2. Brush cap
2
1
Use a screwdriver to remove the caps. 
Take out the worn carbon brushes, in-
sert the new ones and secure the brush 
caps.
Reinstall the brush cap cover on the 
tool.
To maintain product SAFETY and RE-
LIABILITY, repairs, any other mainte-
nance or adjustment should be per-
formed by Panasonic Authorized or 
Factory Service Centers, always using 
Panasonic replacement parts.
VI.  MAINTENANCE
Use only a dry, soft cloth for wiping the 
unit. Do not use a damp cloth, thinner, 
benzine, or other volatile solvents for 
cleaning.
VII. ACCESSORIES
  CAUTION:
• The use of any accessories not  specified in this manual may re-
sult in fire, electric shock, or per-
sonal injury. Use recommended 
accessories only.
• Your tool is supplied with a guard  for use with a grinding disc. A cut-
off disc can also be used with a 
cut-off disc guard. If you decide to 
use your Panasonic grinder with 
approved accessories which you 
purchase from your Panasonic dis-
tributor or factory service center, 
be sure to obtain and use all nec-
essary fasteners and guards as 
recommended in this manual. Your 
failure to do so could result in per-
sonal injury to you and others.
Grinding Disc
• EY9X202E
Wheel diameter 115 mm (4-1/2”) x 
6 mm (1/4”) x 22 mm (7/8”)
Grinding Disc Guard
• EY9X212E
Cut-off Disc
• EY9X203EWheel diameter 115 mm (4-1/2”) x 
2.5 mm (3/32”) x 22 mm (7/8”)
Cut-off Disc Guard (For cut-off disc)
• EY9X213E
Disc Flange
• EY9X221E
Clamp Nut
• EY9X231E
Carbon brush 
						

							- 20 - 
VIII. SPECIFICATIONS
MAIN UNIT
Mounting wheel diameter115 mm (4-1/2”)
Mounting wheel innerhole diameter22 mm (7/8”)
Spindle thread sizeM14
Motor voltage14.4 V DC
Rated speed9500 min
-1 (rpm)
Weight (with battery pack)2.2 kg (4.8 lbs)
Overall length361 mm (14-7/32”)
BATTERY PACK
ModelEY9L40
Storage batteryLi-ion Battery
Battery voltage14.4 V DC (3.6 V x 4 cells)
Capacity3 Ah
BATTERY CHARGER
ModelEY0L80
RatingSee the rating plate on the bottom of the charger.
Weight0.95 kg 
(2.1 lbs)
[Li-ion battery pack]
Charging time3 Ah14.4 V 21.6 V 28.8 V
EY9L40Usable: 35 min.
Full: 50 min.
EY9L60Usable: 45 min.
Full: 60 min.
EY9L80Usable: 55 min.
Full: 70 min.