FEC AFC1500 - Manual (Page 112)

Chapter 6: Fastening Instructions
Page 6-26
6.6.2 Offset Check / Offset Correction
The Offset Check is a function used for determining if there is any prevailing torque/load on the output
drive of the tool assembly during a no load free spinning condition. Any external load sensed by the
Tool’s transducer can detract from torque applied to a fastener during a fastening operation. External
loading can occur as a result of external gearing or linkage to drive that is located after the Torque
transducer. The Offset Check feature checks that the average torque value sensed during Offset
Check Revolutions is below the programmed Offset Torque Limit, otherwise an Abnormal will be gen-
erated upon completion of the Offset Check. Offset Check will run for the full duration of the pro-
grammed Offset Check Revolutions regardless of the amount of load sensed.
WARNING: Care must be taken to ensure that the Offset check is performed only during a free
spinning conditioning. If performed while engaged on a fastener damage may occur.
The Offset Correct feature will correct for the value detected during the last Offset Check and allow
the correct torque to be applied at the output shaft of the external drive system. The Offset Check
must be run each time the system is powered on as the value will be lost after a power down of the
system. If used, it is recommended that the Offset Check is performed at specific intervals through-
out the course of a production day to verify that the value has not changed.
See the AFC User Console software manual for additional set-up information.
Note: In normal operation this is not required, as the FEC torque transducer is located at the
output shaft of the nutrunner tool assembly. FEC spring loaded spindle assemblies have in-
ternal support bearings making external load negligible. This is mainly used when driving
through external gearing.
6.6.3 Angle Correction
An Angle Correction preset is available for correcting angle reading disparities during calibration us-
ing a certified master transducer with Angle Monitoring capabilities. Under normal conditions this is
not used. This may be necessary in applications requiring crowsfeet, right angle drives, belt or chain
drives, etc.
Setting range is from -99 to +99 degrees.
See the AFC User Console software manual for additional set-up information.
6.6.4 One Pulse Reverse Function
One Pulse Reverse is used in applications where socket to fastener tolerances allow the fastener to
“stick” or lock into the socket during fastening operations. Upon completion of Fastening, torque is
applied in the reverse direction for the full time specified by 1 Pulse Reverse Time, at the speed spe-
cified by 1 Pulse Reverse Speed, allowing the socket to free itself from the fastener. This is done
without affecting the torque originally applied to the fastener by setting the 1 Pulse Reverse Torque
Limit to a lower Torque value.
See the AFC User Console software manual for additional set-up information.