92
P a r r I n s t r u m e n t C o m p a n y
4848 Reactor Controller
3B. Motor Control Module (MCM)
In this configuration, the module provides
true closed loop feedback control of the reac-
tor stirring speed. The primary output of this
module is wired to dynamically adjust the motor
voltage in response to changes in motor load-
ing. This provides better reactor stirring speed
regulation than the standard open loop speed
control, especially with reactions that involve
changing viscosities. Additionally, the use of
this module allows the stirring speed set point
to be adjusted remotely from the host PC. A by-
product of this closed loop speed control scheme
is that the value of the primary controller output
directly reflects the degree of loading on the
motor in order to maintain a constant stirring
speed. While not a direct torque measurement,
this is a useful option for those who want to, for
example, monitor the progress of polymeriza-
tion reactions in which there is a change in
viscosity as the reaction proceeds. The output
to the motor can be displayed and logged on
the PC when used with the A3504HC Specview
Software.
4. Motor Torque Module (MTM)
The MTM will display motor output from an
MCM. It is particularly useful for applications
with changing viscosities.
5A. High Temperature Cut Off Module
(HTM)
The high temperature cut off module or limit
controller augments the operation of the main
control module. Its redundant sensor can be
mounted either internally or externally to the
reactor. The primary output of the module is
wired to activate the lock out relay in order to
provide safety shutdown should the reactor
reach an unsafe temperature.
4848 back panel for 115V model.
The expanded 4848B Reactor Controller is designed for those
who need up to six expansion modules for their reactor system.
5B. External Temperature Limit Module
(ETLM)
This configuration uses the same aforemen-
tioned HTM Module with its sensor mounted in
such a way to monitor the reactor’s outside wall
temperature. The primary output of this module
is used to limit the external temperature of the
reactor. This is done by interrupting the control
signal form the main temperature controller
when the external temperature exceeds a pre-
determined value. The secondary output of this
module is used to activate the lock out relay if
the outside wall temperature exceeds a preset
unsafe temperature. The use of this module
provides and effective alternative to cascade
control, offering improved temperature regula-
tion in systems with large thermal lags, such as
those found in non-stirred reactors or systems
that use PTFE liners, as well as systems where
the reactants have low heat capacities, such as
gas phase reactions.
6. Solenoid Valve Module (SVM)
This package includes a solenoid valve and
a flow adjustment valve with all of the parts
required to assemble an automatic system to
control the flow of coolant thru a cooling coil
in any reactor. It plugs into the cooling output
socket on the 4848. It is designed for use with
tap water as the cooling media.
