Barnes thermoplay TH-M6, User Manual

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At every successive start, heating begins with the same parameters active during the last stop.
The zone parameters calculated automatically during the tuning phase are: “Pb” (Idx 14), “Int”
(Idx 15), “Der” (Idx 16), “Fuzzy overshoot control”
(Idx18).
If the Auto tune function is enabled, after the Soft Start, the heating goes on until 75% (common
parameter “% SP end Soft Start - start Auto Tuning” (Idx 1)) of the active set point.
Independently, each zone starts the tuning procedure (the displayed status is “TUNE”).
It is normal that the duration of auto-tuning phase is different on each zone (longer in the
zones with bigger thermal inertia).
Only when all the zones have finished the procedure (status of all the zones is back to “AUTO”)
normal heating restarts until the set point is reached.
Note: regardless of common parameter “% SP end Soft Start - start Auto Tuning” (Idx 1), Auto Tuning is inhibited if
at the heating start current temperature is higher than 75% of the Set Point.
See paragraphs 6.13 and 6.144 for zone and common parameters specifications.
4.3 Soft start
During the soft start phase the power output is limited by a maximum value of 15% (default
value of zone parameter “Output power high limit during Soft Start” (Idx 6)). In the status area
appears “SOFT”. In case of brief interruption, soft start is automatically deactivated: it is sufficient
that the temperature of one zone is superior to the level of inhibition temperature set (common
parameter “Temperature threshold to abort Soft Start” (Idx 16).
4.4 Synchronous heating
A delayed start-up of the nozzles (and in general of low thermal inertia) in respect to the
manifold zones (high thermal inertia) is no longer necessary: all the zones follow the same
incremental temperature ramp. In this way, the set point is reached contemporaneously (the
tolerance is given by the common parameter “Synchronous heating tolerance” (Idx 5)) in all the
elements of the injection system avoiding problems such as material degradation for excessive
time at high temperature.
4.5 Automatic mode (closed loop)
In “
automatic
” mode the power supplied on the load is automatically set by the temperature
controller. The operator can modify the value of the set point, not the percentage power
supplied.
If the temperature controller finds an anomaly on the thermocouple, the power
supplied is immediately 0%
(zone parameter “Security power” (Idx 9)).
4.6 Manual mode (%)
In “ manual ” mode the temperature controller supplies the load with the power value set by
the operator. The set point is no longer active. The temperature controller could work in this
mode even in the case of thermocouple failure.