Armfield Instruction Manual
16
Default PID Settings for the Hot Water Circulator:
Process variable = Hot Water Temperature (T2)
Control Variable = Heater
Control Action = Reverse
SP = Chosen by the user IT = 0 Cycle time = 10
PB = 1% DT = 0
Operating the CEM MKII
Temperature T1 in the reactor is monitored on the software and is controlled by
circulating heating or cooling liquid through the internal coil.
There are two modes of operation with the CEM: Experiment with HEATER and with
CHILLER.
When using the Chiller CW-17 PID settings are not required. See the Installation
section for appropriate controller settings when using the CW-17.
When using the Heater the temperature sensor T1 supplied with CEXC, which is
Reactor Temperature on the software, should be set as the Process Variable to be
controlled in the PID loop. This sensor must be immersed in the reactor vessel and
will be data logged.
The volumetric ratio in which the reactants are mixed is defined by the relative flow
rates of the two pumps. If the pumps are operated at the same flow rate then the
reactants are mixed in equal volumes.
The degree of mixing may be adjusted using the agitator speed control box on the
main screen of the software.
The extent of conversion of the reactants is determined from the conductivity, which
is measured by the conductivity probe.
