Powerware ST-2400S User Manual

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and the RPM sensor gear.  Make sure that they are not loose 
and that the runout of the RPM gear is not excessive. Check 
the RPM sensor connector to be sure that it is tight. Check 
the cable from the RPM pickup to the horsepower computer.  
Check the power supply to the horsepower computer. Have 
the horsepower computer checked. 
Torque readings are 
inaccurate 
Operate the unit using the ZERO and CHECK functions.  If 
the readings do not agree with the tables above, unit needs 
to be repaired. Check the load cell mounting to be sure that 
it is not loose. Check the dynamometer to be sure that it is 
not in a bind. Check the torque calibration of the 
horsepower computer.  Check the power supply to the 
horsepower computer. Have the horsepower computer 
checked. 
Residual Torque readings 
are high when the 
dynamometer is stopped. 
Pressure or force on the dynamometer absorption unit cradle 
may be causing the residual readings. Remove the load cell 
from the torque arm of the dyno to see if this removes the 
excessive residual torque reading. Manually rock the torque 
arm of the dyno.  It should move freely and easily a 
minimum of 0.5 inches (12.7 mm) up and down.  The load 
cell must be in a free floating position when not under load. 
Re-adjust the torque cable and connectors if necessary.  
Check the calibration zero of the horsepower computer.  
The load cell may be damaged and need to be replaced.  
Have the horsepower computer checked. 
 
 
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