Atlas Copco PowerMACS 4000, User Manual

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Tightening
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Result var.:
"Bolt T" and ”Bolt T2nd” (measured on the second monitoring buffer)
Alarms: Final torque too high (FTHM, FTHM2), Final torque too low (FTLM, FRLM2). FTHM2 and
FTLM2 are used for check errors on the second monitoring buffer. If Bolt T is less than the
value specified by the Program Settings parameter
Report threshold torque limit then the
warning bit REPLIMIT is set. This does not generate an event unless all bolts that where
run during a cycle sets REPLIMIT. If so, the station issues an event (event code 628) to
inform that the cycle data was dropped.
Trace : FTH and FTL are shown in trace as horizontal lines from monitoring start to monitoring stop.
The lines are only shown when Torque vs. Angle is selected and Monitoring limits are
enabled in the trace form (see
View of trace curves).
6.6.2 Monitoring Check
– Angle
User Interface:
Parameters: Fatal , Monitoring buffer , AH (High level), AL (Low level), Tstart (Torque Level, Tstart),
Tstop (Torque Level, Tstop), Torque falling below Tstop .
Function: This function checks that the angle A is within the specified limits AH and AL . Angle A is
measured from the point where the torque has reached Tstart (Astart) until the point where
the torque reaches Tstop (Astop).
Depending on the configuration of
Tstart , Tstop and Torque falling below Tstop one of
two basically different methods for data collection is used. If Tstart and Tstop both are left
empty, or Tstop is specified and Torque falling below Tstop is checked, then Astart and
Astop are continuously searched for during the cycle. This is the Runtime method. For all
other settings the buffer method is used, which means that Astart and Astop are searched
for in the buffer.
The Buffer method:
Astart is defined as the angle in the buffer where the torque first exceeds Tstart . If Tstart is
empty Astart is defined as the angle at buffer start. Astop is defined as the angle in the
buffer where the torque first exceeds
Tstop (this is Astop
1
in the below picture). If Tstop is
left empty Astop is defined as the maximum angle reached (Aend
1
in the picture).
The Runtime method: