BAC 3872C - Page 14

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• Belt tension check:
– PlaceastraightedgealongthebeltfromsheavetosheaveasshowninFigure 3a,or
useatapemeasureasshowninFigure 3btomeasurebeltdeection.
– Applyamoderateforcebyhand(approximately40lbs/275kPa)evenlyacrossthe
widthofthebeltinthecenterofthespanbetweenthesheaves.
– Thereisadequatebelttensionifthebeltdeectsbetween1/4”and3/8”asshown
in Figures 3aand3b.
NOTE: If belts are properly
tensioned, there should be no
“chirp” or “squeal” when the fan
motor is started.
ATTENTION: Check to ensure the
controls for the fan motor are set
to allow a maximum of six on-off
cycles per hour to prevent motor
overload.
Figure 3a. Belt Tension with a Straight Edge
Figure 3b. Belt Tension with a Tape Measure
• Belt tension adjustment (if required):
– Loosenthelocknutonthemotorbaseadjustingscrew.
– Turnthemotorbaseadjustingscrewclockwiseto
tensionthebeltorcounterclockwisetorelievebelt
tension.Duringadjustmentofthebelttension,rotate
thedrivesseveraltimesbyhandtoevenlydistribute
thetensionthroughoutthebelt.
– Whenthebeltisproperlytensioned,retightenthe
lockingnutonthemotorbaseadjustingscrew.
• Drive alignment check and adjustment:
– Checkthedrivealignmentannuallytoensure
maximumbeltlife.
– Placeastraightedgeacrossthedriverandthedriven
sheavesasshowninFigure 4a forstandarddrivesand
inFigure 4bfortheBALTIGUARD™FanSystemorthe
BALTIGUARDPLUS™FanSystem.
– Thestraightedgeshouldcontactallfourpointsas
showninFigure 4aindicatingthatthedrivesare
properlyaligned.
– Thereshouldbenomorethan1/16”deviationfrom
thefourpointsofcontact.
– Incaseofrealignment,loosenthemotorsheave,and
alignitwiththefansheave.Allow1/4”fordraw-upas
thebushingscrewisretightened.
Figure 4a. Standard Drive Alignment
Figure 4b. BALTIGUARD™/BALTIGARD PLUS™ Fan System Drive Alignment