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To accept the new setting and access the cut-out set-point press "SET". Press-
ing "EXIT" exits the secondary menu ignoring any changes just made to the
proportional band value.
S
9.8
Cut-out
As a protection against software or hardware fault, shorted heater triac, or user
error, the bath is equipped with an adjustable heater cut-out device that shuts
off power to the heater if the bath temperature exceeds a set value. This protects
the heater and bath materials from excessive temperatures and, most impor-
tantly, protects the bath fluids from being heated beyond the safe operating
temperature preventing hazardous vaporization, breakdown, or ignition of the
liquid. The cut-out temperature is programmable by the operator from the front
panel of the controller. It must always be set below the upper temperature limit
of the fluid and no more than 10 degrees above the upper temperature limit of
the bath.
If the cut-out is activated because of excessive bath temperature then power to
the heater is shut off and the bath cools. The bath cools until it reaches a few
degrees below the cut-out set-point temperature. At this point the action of the
cut-out is determined by the setting of the cut-out mode parameter. The cut-out
has two selectable modes — automatic reset or manual reset. If the mode is set
to automatic, then the cut-out automatically resets itself when the bath tempera-
ture falls below the reset temperature allowing the bath to heat up again. If the
mode is set to manual, then the heater remains disabled until the user manually
resets the cut-out.
The cut-out set-point may be accessed within the secondary menu. Press "SET"
and "EXIT" to enter the secondary menu and show the heater power. Then
press "SET" twice to access the cut-out set-point.
S+E
12 Pct
S
Pb=0.101C
S
CO= 210C
Accept the new proportional band setting
Access heater power in secondary menu
Heater power in percent
Access proportional band
Proportional band setting
Access cut-out set-point
Cut-out set-point
9 Controller Operation
Cut-out
45
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