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Belt Tensioning:
The belts are adjusted by tensioning bolts which adjust the motor base. Check
tension frequently during the first 24-48 hours of run-in operation. To properly
adjust the belt tension, position the fan motor so that moderate pressure on
the belt midway between the sheaves will produce a 13mm deflection. Over-
tensioning shortens belt and bearing life. Keep belts free from foreign material
which may cause slipping. Never apply belt dressing as this will damage the
belt and cause early failure. A Dodge
®
V-Belt Tension Tester or similar device is
an alternate method for tensioning V-belts. Check with you local belt supplier.
Sheave Alignment:
• The motor sheave is to be positioned as close as possible to the motor
in order to minimize torque on the motor bushings.
• The motor and fan sheaves may have grooves that are not used. The bot-
tom surface of the motor and fan sheaves must be aligned within 3mm of
each other and level within ½° (3mm in 300mm) in order to not adversely
affect belt and sheave life.
• Alignment can be achieved by placing a straight edge across the top of
the sheaves making sure that it is level and measuring down to the bottom
surface of both sheaves at four points.
• The belts are to be located in the inboard set of grooves closest to the
bearing.
maintenance
➠
SHEAVE
STRAIGHT EDGE
SHEAVE
THREADED ROD
FAN SHAFT
