NBE Brawn mixer BTO Series, Operation And Maintenance Manual

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BTO-S
ERIES
O
PERATION
& M
AINTENANCE
M
ANUAL
12838 Stainless Drive, Holland, MI 49424 Phone: 616/399-5600 Fax 616/399-3084
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Copyright 2018 BRAWN Mixer www.BRAWNMIXER.com Page 6 of 9
11/27/2018
ELECTRIC MOTORS, Cont.
BEARING LUBRICATION
CAUTION
Do not lubricate motor while in operation, since excess
grease will be forced through the bearings and into the
motor before it will force its way out of the drain plug.
Excess grease accumulation on windings reduces
insulation life.
Prior to shipment, motor bearings are lubricated with the
proper amount and grade to provide six months of
satisfactory service under normal operation and
conditions.
For best results, grease should be compounded from a
polyurea base and a good grade of petroleum oil. It
should be of No. 2 consistency and stabilized against
oxidation. Operating temperature ranges should be from
-15°F to +250°F for class B insulation, and to +300°F for
classes F and H. Most leading oil companies have
special bearing greases that are satisfactory.
Relubricate bearings every six months (more often if
conditions require) as follows:
1. Stop the motor. Lock out the switch.
2. Thoroughly clean off pipe plugs and remove
from housings.
3. Remove hardened grease from drains with a stiff
wire or rod.
4. Add grease to inlet with hand gun until small
amount of new grease is forced out drain.
5. Remove excess grease from ports, replace inlet
plugs, and run motor ½ hour before replacing
drain plug.
6. Put motor back in operation.
INSULATION RESISTANCE
Check insulation resistance periodically. Any approved
method of measuring insulation resistance may be used,
provided the voltage across the insulation is at a safe
value for the type and condition of the insulation. A hand
crank megger of not over 500 volts is the most
convenient and safe method. Standards of the Institute
of Electrical and Electronics Engineers, Inc., recommend
that the insulation resistance of the stator windings at 75°
C, measured at 500 volts dc, after one minute should not
be less than:
Rated Voltage of M 1000
=
Insulation Resistance
1000 in Megohms
This formula is satisfactory for most checks. For more
information, see IEEE Standard No. 43 “Recommended
Practice for Insulation Resistance Testing of AC Rotating
Machinery.”
CLEANING
WARNING
Do not attempt to clean the motor while it is operating.
Contact with rotating parts can cause severe personal
injury or property damage. Stop the motor and lock out
switch before cleaning.
The motor exterior must be kept free of oil, dust, water,
and chemicals. For fan-cooled motors, it is particularly
important to keep the air intake openings free of foreign
material. Do not block air outlet or inlet.
On non-explosion-proof TEFC motors, a removable plug
in the bottom center of the motor frame or housing
permits removal of accumulated moisture. Drain
regularly.
MAINTENANCE / LUBRICATION
Gear units should have the oil changed every 10,000
hours or 2 years. If synthetic lubricant is used, it should
be changed every 20,000 hours or 4 years. For adverse
operating conditions, the interval should be shorter.
DO
NOT MIX SYNTHETIC AND MINERAL BASED OILS.
Units should be checked periodically for increased noise,
surface temperature, vibration, shaft movement and
amperage draw. Units with inspection covers should not
be operated with the inspection cover removed.
CAUTION
Oil should be changed more often if reducer is used in a
severe environment (i.e., dusty, humid).