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User's Guide
38
The proportional band adjustment may be accessed within the secondary menu.
Press “SET” and “EXIT” to enter the secondary menu and show the heater
power. Then press “SET” to access the proportional band.
+
Access heater power in secondary menu
Heater power in percent
Access proportional band
Proportional band setting
To change the proportional band press “UP” or “DOWN”.
New proportional band setting
To accept the new setting and access the cutout set-point press “SET”. Pressing
“EXIT” exits the secondary menu ignoring any changes just made to the
proportional band value.
Accept the new proportional band setting
Cutout
As a protection against software or hardware fault, shorted heater triac, or user
error, the bath is equipped with an adjustable heater cutout 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
importantly, protects the bath fluids from being heated beyond the safe operating
temperature preventing hazardous vaporization, breakdown, or ignition of the
liquid. The cutout 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 cutout is activated because of excessive bath temperature then power to
the heater shuts off and the bath cools. The bath cools until it reaches a few
degrees below the cutout set-point temperature. At this point the action of the
cutout is determined by the setting of the cutout mode parameter. The cutout has
two selectable modes — automatic reset or manual reset. If the mode is set to
automatic, the cutout automatically resets itself when the bath temperature falls
below the reset temperature allowing the bath to heat up again. If the mode is set
to manual, the heater remains disabled until the user manually resets the cutout.
The cutout 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 cutout set-point.
12 Pct
Pb=0.101C
Pb=0.060C