3
MN903
Electrical Instructions
Single phase grinders are rated dual voltage. Some single phase grinders are equipped with cord and grounding
type plug for 115 volts. To use with a different voltage, see instructions provided to make wiring changes. All
attachment plugs and any receptacles must be replaced with devices rated for the voltage for which the grinder is
reconnected. Table 1 indicates the minimum wire size. Be sure to comply with NEC and local wiring codes.
Three phase grinders are normally dual voltage and must be wired for the proper voltage and rotation direction
(connections are inside conduit box). Connect phase sequence so that the wheel moves down toward top surface
of tool rest as viewed from front of grinder. Wheel must rotate toward tool rest. Be sure all electrical connections are
secured and properly insulated. For your safety, be certain grinder is properly grounded.
Grounding Instructions
WARNING:
Be sure the system is properly grounded before applying power. Do not apply power before you ensure that
grounds are connected. Electrical shock can cause serious or fatal injury. Follow the National Electrical Code
(NEC) and local codes for the safe installation of this equipment.
1. All grounded, cord-connected grinders:
In the event of a malfunction or breakdown, grounding provides a path of least resistance for electric current to
reduce the risk of electric shock. This grinder is equipped with an electric cord having an equipment-grounding
conductor and a grounding plug. The plug must be plugged into a matching outlet that is properly installed and
grounded in accordance with all local codes and ordinances. Do not modify the plug provided. If it will not fit the
outlet, have the proper outlet installed by a qualified electrician.
Improper connection of the equipment-grounding conductor can result in a risk of electric shock. The “Green”
insulated wire (with or without yellow stripes) is the equipment-grounding conductor. If repair or replacement of
the electric cord is necessary, do not connect the equipment-grounding conductor to a live terminal.
Check with a qualified electrician or serviceman if the grounding instructions are not completely understood, or
if in doubt as to whether the tool is properly grounded.
Use only 3-wire extension cords that have 3-prong grounding plugs and 3-pole receptacles that accept the
tool’s plug.
Repair or replace damaged or worn cord immediately.
2. Grounded, cord-connected grinders intended for use on a supply circuit having a nominal rating less than 150 volts:
This grinder is intended for use on a circuit that has an outlet that looks like the one illustrated in Figure A or B.
Figure A
Grounding
Blade
Figure B
Grounding
Blade
Cover of
Grounded
Outlet Box
3. Permanently connected grinders:
This grinder should be connected to a grounded, metal, permanent wiring system; or to a system having an
equipment-grounding conductor.
Operation
WARNING:
Do not operate this grinder until you are sure that you are completely familiar with the safe operation of the
grinder, all accessories and safety equipment. Improper use can lead to severe injury. This manual defines
proper use of this equipment. Before using this equipment for any other use, please consult Baldor. Contact
Baldor if you do not understand any procedure or operation concerning this grinder or this manual.
WARNING:
When starting a grinder for the first time, or after installing a replacement grinding wheel, it is most important
that the operator stand aside for at least one minute of rotation at full speed. This is the correct practice
since grinding wheels can disintegrate if they have received damage during shipping or handling.
Check that the On-Off switch is in the “OFF” position, and the grinding wheel and wheel move freely. When starting
the grinder for the first time or after replacing a wheel, it is important that the operator stand aside for at least one
minute of operation at speed. This will ensure that operation will be safe from debris. After connecting grinder to
power source, turn switch on. Grinder should come up to speed smoothly and without vibration. If grinder does
not, shut grinder off immediately and determine reason.
As grinding wheel wears, maintain 1/8” or less clearance between tool rest and grinding wheel and spark arrestor
and grinding wheel.
Grind on grinding face (periphery) of wheels only.