Koehler K87170, Operation And Instruction Manual

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f.
Condenser Temperature : Set the temperature of the condenser
coolant to at least 30 ºC below the lowest vapor temperature to be
observed in the test. A suitable coolant temperature for most
distillations is 60 ºC.
g. Pressure Step Down Rate: This the rate at which pressure will be
reduced before the distillation begins. Pressure step down begins at
100 mmHg and is reduced from there at the desired rate. Slow
reduction in pressure helps to prevent foaming by allowing the sample
to slowly degas before the distillation begins.
h. Maximum Vapor AET : This is an optional field in case there is a
need to stop the distillation at a specific vapor temperature. If the field
is left blank, it appears grey and is ignored. If the field has a value
entered then, the distillation will stop at that atmospheric equivilant
temperature (AET).
i. Distillation PID Bias: This is the starting point for the distillation
rate control. If the distillation rate is too high then lower this value. If
the distillation rate is too low during then raise this value. Normally
the default value is suitable.
j. Stop by volume : If this box is checked, then an additional field
appears. This is an optional field in case there is a need to stop the
distillation at a specific volume % distilled. If the box is not checked
then the field is ignored. If the box is checked the the distillation will
stop at the volueme % entered in the field.
k. Stop on cracking detection : This is an optional function. When
check, the system will monitor the system for signs of cracking of the
sample. If sample cracking is observed, the distillation will stop
automatically. If the box is left unchecked, then this function is
disabled.
Operating the Microprocessor Controller 4-6