Parr Instrument 4838 Instruction Manual

4838
Reactor Controller
Operating Instruction Manual

Table of Contents
2
Table of Contents
Preface
Related Instructions — 3
Scope — 3
Applications — 3
Explanation of Symbols — 4
Safety Information — 4
Provisions for Lifting and Carrying — 4
Intended Usage — 4
Cleaning & Maintenance — 4
General Specifications — 5
Environmental Conditions — 5
4838 Reactor Controller Specifications — 5
User’s Responsibility — 6
Unpack Carefully — 6
Installation
General Instructions — 7
Connections — 7
Component Summary
Switches and Indicators — 8
Protective Fuses and Relays — 8
High Limit Reset — 9
Access to the Controller Cabinet — 9
Fuses — 9
Instructions for the 4838 Reactor Controller
Temperature Control Module — 10
Communication with PC — 16
4838 Factory Defaults
Navigating the Menu System / Factory Default Settings — 18
PrimaryTemperature Module — 18
Pressure Module — 19
HTM / ETLM Module — 20
Appendix A: Controller Parameters
Initial Setting Mode — 21
Operation Mode — 22
Regulation Mode — 23
Parts List
Fuses — 24
PrimaryTemperature Module — 24
Pressure Display Module (PDM) — 25
Hi-Temp Cut-Off Module (HTM) — 26
or ExternalTemperature Limit Module (ETLM) — 26

4838 Reactor Controller
3
Preface
Related Instructions
The following publications are also included to
further your understanding of this instrument and
its component parts:
No. Description
201M Limited Warranty
552M CD for 4838 Controller
Scope
These instructions cover the installation and opera-
tion of Model 4838 Reactor Controller as used
with Laboratory Reactors and Pressure Vessels.
They cover the basic functions provided in each of
these controllers and describe the several optional
control modules which can be added to these ex-
pandable units. The users should study the instruc-
tions carefully before using any of these controllers
so that they will fully understand the capabilities
of this equipment and the safety precautions to be
observed in its operation.
Applications
Each 4838 Reactor Controller consists of a packaged
temperature control unit completely wired and as-
sembled with appropriate power and safety relays,
switches and pilot lights.
These units are designed specifically for use with
pressure vessels and are to be used only with
equipment.

4838 Reactor Controller
4
Explanation of Symbols
II On position, full power heater switch
I On position, half power heater switch
O Off Position
~ Alternating Current (AC)
This CAUTION symbol may be present on the Product Instrumentation
and literature. If present on the product, the user must consult the ap-
propriate part of the accompanying product literature for more infor-
mation.
Protective Earth (PE) terminal. Provided for connection of the protec-
tive earth (green or green/yellow) supply system conductor.
Intended Usage
This controller has been designed for use with
pressure vessels and reactors. It has been de-
signed, built, and tested to strict physical and electri-
cal standards. However, it is the user’s responsibil-
ity to install and operate it in conformance with local
pressure and electrical codes.
If the instrument is used in a manner not specified
by Company, the protection provid-
ed by the equipment may be impaired.
Cleaning & Maintenance
Periodic cleaning may be performed on the exterior
surfaces of the controller with a lightly dampened
cloth containing mild soap solution. All power
should be disconnected and the power cord should
be unplugged when cleaning the 4838 Controller.
There are no user serviceable parts inside the prod-
uct other than what is specifically called out and
discussed in this manual. Advanced troubleshooting
instructions beyond the scope of this manual can
be obtained by calling Company in
order to determine which part(s) may be replaced or
serviced.
Ensure that any hot surfaces have had ad-
equate time to cool before cleaning or main-
taining the reactor and/or its components.
Safety Information
To avoid electrical shock, always:
1. Use a properly grounded electrical outlet of cor-
rect voltage and current handling capability.
2. Ensure that the equipment is connected to elec-
trical service according to local national electri-
cal codes. Failure to properly connect may create
a fire or shock hazard.
3. For continued protection against possible haz-
ard, replace fuses with same type and rating of
fuse.
4. Disconnect from the power supply before main-
tenance or servicing.
To avoid personal injury:
5. Do not use in the presence of flammable or com-
bustible materials; fire or explosion may result.
This device contains components which may
ignite such material.
6. Refer servicing to qualified personnel.
Caution!
Do not use in hazardous atmospheres.
Provisions for Lifting and Carrying
Before moving the instrument, disconnect all con-
nections from the rear of the apparatus. Lift the
instrument by grabbing underneath each corner.

4838 Reactor Controller
5
General Specifications
Electrical Ratings
115VAC, 15.0 Amps, 50/60 Hz
230VAC, 15.0 Amps, 50/60 Hz
Before connecting a controller to an electrical outlet,
the user must be certain that the electrical outlet has
an earth ground connection and that the line, load
and other characteristics of the installation do not
exceed the following limits:
Voltage: Fluctuations in the line voltage should not
exceed 10% of the rated nominal voltage shown on
the data plate.
Frequency: Controllers can be operated from either
a 50 or 60 Hertz power supply without affecting their
operation or calibration.
Current: The total current drawn should not exceed
the rating shown on the data plate on the controller
by more than 10 percent.
Thermocouple: Unless otherwise specified, all 4838
Controllers operate with aType-J (Iron-Constantan)
thermocouple. The total resistance of the thermo-
couple and the lead wires should not exceed 100
ohms. If the resistance of the thermocouple circuit
is higher, it will not function properly.
Environmental Conditions
This instrument is intended to be used indoors.
Operating: 15 ºC to 35 ºC; maximum relative humid-
ity of 80% non-condensing. Installation Category II
(over voltage) in accordance with IEC 664.
Pollution degree 2 in accordance with IEC 664.
Altitude Limit: 2,000 meters.
Storage: -25 ºC and 65 ºC; 10% to 85% relative hu-
midity.
4838 Reactor Controller Specifications
General Specifications
InputThermocouple type Type-J
Operating Range 0-800 °C
Readout and Setpoint
Resolution
1 °C
System Accuracy +/- 2 °C
Control action three-term PID plus limit
control
Control output 1 115VAC or 230VAC
Operating voltages 115VAC or 230VAC
Heater Loop
Proportional Band: 12 °C
Integral time: 375 seconds
Derivative: 93 °C/second
Cycle time: 20 seconds

4838 Reactor Controller
6
User’s Responsibility
All Reactors and Pressure Vessels are designed
and manufactured with great care to assure safe
operation when used within their prescribed tem-
perature and pressure limits.
But… the basic responsibility for safety when us-
ing this equipment rests entirely with the user; who
must:
1. Select a reactor or pressure vessel that has the
capability, pressure rating, corrosion resistance,
and design features that are suitable for its
intended use. ynapmoC engineers will be glad to dis-
cuss available equipment and material options
with prospective users, but the final responsi-
bility for selecting a reactor or pressure vessel
that will perform to the user’s satisfaction in any
particular reaction or test must rest with the user
In exercising the responsibility for the selection
of pressure equipment, the prospective user
is often faced with the choice between over or
under-designed equipment. The hazards intro-
duced by under-designed pressure vessels are
readily apparent, but the penalties that must be
paid for over-designed apparatus are often over-
looked. Recognizing these criteria, reac-
tors and pressure vessels are offered in several
different styles, each designed for convenient
use in daily operation within certain temperature
and pressure limits, using gaskets, closures, and
other elements carefully selected for safe opera-
tion within the limits specified for that design.
But in order to preserve the validity of these de-
signs, all temperature and pressure limits must
be observed, and no attempt should be made to
increase these limits by making alterations or by
substituting components which are not recom-
mended by Company.
2. Install and operate the equipment within a
suitable barricade, if required, with appropriate
safety accessories and in full compliance with
local safety codes and rules.
All standard pressure vessels are provided
with either suitable relief device or a means to
attach one (typically in the form of a plugged
opening). When a pressure vessel is delivered
without a pressure venting device, it is the cus-
tomer’s responsibility to provide pressure relief
in order to protect the operator and the equip-
ment from destructive high pressures. If you
need more information or need help in selecting
a proper relief device, please contact
Company.
3. Establish training procedures to ensure that any
person handling the equipment knows how to
use it properly.
4. Maintain the equipment in good condition and
establish procedures for periodic testing to be
sure the vessel remains structurally sound.
Unpack Carefully
Unpack the equipment carefully and check all the
parts against the packing list. If shipping damage
is discovered, report it immediately to the deliver-
ing carriers. Examine the components closely for
any loose parts or shipping damage and be sure to
check all layers of packing materials thoroughly so
as not to overlook any parts which might otherwise
be discarded.

4838 Reactor Controller
7
Installation
General Instructions
Set the controller on a sturdy bench or table where
there is convenient access to an electrical outlet
with the appropriate supply voltage and current rat-
ings in accordance with national and local electrical
code requirements. Leave a space of at least twelve
inches between the controller and the heater of the
reactor so that the controller will not be affected by
radiant heat.
Connections
Labeled connections are provided on the rear panel
of the controller.
Heating Only
The heating output connector is to be used only
with Company heater assemblies
supplied with the appropriate heater power cord.
The Primary Temp Input connection is for the Pri-
maryTemperature Module sensor input.
The Temperature Input connection is for theTem-
perature Module or ETLM sensor input.
The Pressure Input connection is for the Pressure
Module sensor input.
The Comm connector is for Communication output.
4838 Rear Panel 115V
4838 Rear Panel 230V

4838 Reactor Controller
8
Component Summary
Switches and Indicators
Front side
4838 Reactor Controller
The Heater Switch is a manual, three-position, illu-
minated switch which controls the amount of power
sent to the heater. In the HIGH (II) position, full
power is developed by the heater. In the middle (0)
position the heater is off. In the LOW (I) position, a
diode is switched into the system to allow only one-
half of the rated voltage to be supplied to the heater.
This low setting will be most useful when operating
the reactor at temperatures below 175 °C. Power
for the heater is supplied through a solid state relay
controlled by the temperature control module. The
light in the heater switch will glow only when cur-
rent is flowing to the heater.
The high limit indicator light will glow if the control-
ler receives an indication from any of its sensors
that a high temperature or high pressure limit has
been reached and the High Limit Reset has opened.
When the light comes on, the user must find the
source of the problem, correct it, and then manually
reset the system using the high limit reset button on
the front of the controller.
The Main Power Switch will cut off power to the
controller.Take care to position the controller such
that the main power switch may be accessed easily
when the controller needs to be disconnected.
Back side
4838 Reactor Controller 115V
Protective Fuses and Relays
An instrument fuse is mounted on the back panel.
This is a Fast-acting, 250VAC, 1.0 amp fuse, intended
to protect the temperature control module and any
installed display modules.
A load fuse is mounted on the back panel on 115V
systems. This fast-acting, 250VAC, 20 amp fuse is in-
tended to protect the controller and prevent electric
shock hazard from fault from occurring.
Two load fuses are mounted on the back panel
on 230V systems. These are fast-acting, 20 Amp,
250VAC and are intended to protect the controller
and to prevent electric shock hazard from fault from
occurring.
Caution!
Unplug unit before servicing. For continued
protection against possible hazard, replace
fuses with same type and rating of fuse.

4838 Reactor Controller
9
Back side
4838 Reactor Controller 230V
Thermocouple burnout protection is included in
each of these controllers. If the thermocouple
should burn out, or if there is a break in the thermo-
couple circuit, power to the heater will be shut off.
In most cases this will cause the controller to show
a “NO CONN” reading. A similar high reading will
be displayed if the controller is turned on without an
attached thermocouple. In either of these situations,
the high limit reset will activate. The thermocouple
break must then be corrected and the High Limit Re-
set must be reset in order to activate the system.
High Limit Reset
Each Series 4838 Controller has a high temperature
limit control which will trip the High Limit Relay
and shut off the heater if the temperature reaches
a preset level. If tripped, the lockout relay will pop
out, thereby preventing the system from reheating
the reaction when the temperature falls back below
the limit setting. This must be manually reset before
heating can occur again.
On Model 4838 Controllers the high temperature
limit is preset at the factory to 375 °C for most sys-
tems. On these controllers an alarm condition is
indicated by an illuminated red indicator labeled as
"ALM". If the temperature exceeds the limit, the con-
troller alarm condition will appear, the High Limit
Reset will be tripped, and power to the heater will
be shut off.
Access to the Controller Cabinet
To open the controller cabinet, unplug the power
cord and remove the two screws in the upper
corners of the back panel. Then lift the top plate
upwards, allowing the hinged top and front panel to
swing forward, providing full access to all internal
components.
Caution!
Inside of controller cabinet should be ac-
cessed by qualified personnel only.
Fuses
The 4838 Controller has a number of fuses which
are intended to be field serviceable.
Fuse Rating Part number
Instrument
Fuse
Fast acting, 1
Amp, 250VAC
139E6
Line Fuse(s) Fast acting, 20
Amp, 250VAC
2074E
Caution!
Unplug unit before servicing. For continued
protection against possible hazard, replace
fuses with same type and rating of fuse.

4838 Reactor Controller
10
Instructions for the 4838 Reactor
Controller
Caution!
Check that controller settings are set to
factory defaults before operating for the first
time. The default settings are listed at the
back of this manual.
Note: Controller parameters can be found in
Appendix A on page 21 of this manual.
Temperature Control Module
PRIMARY
TEMPERATURE
The 4838 Reactor Controllers have a microprocessor
based control module that provides full three-term
PID control with adjustable tuning parameters. The
temperature control interface is labeled as Primary
Temperature on front panel.
To facilitate start up with reasonably good PID con-
trol, parameters for both heating and cooling are
pre programmed at the factory.
Output 1 on these controllers drives the heater. Out-
put 2 is not used on the 4838 Controller. The control
parameter can be set independently for this output.
Two lines of information, labeled PV and SV, are
shown on the display during normal operations.
The upper line (PV) shows the actual temperature
as read by the control thermocouple. The lower
line (SV) shows the set point. When the controller
is heating, the Out1 light will illuminate or blink.
When an alarm condition has been reached, the
ALM light will illuminate and trip the High Limit
Reset, cutting power to the heater.
Temperature Control
The easiest way to control temperature with the
4838 Controller is to use setpoint control. With set-
point control, the controller will attempt to bring the
temperature to the value of the setpoint by adjust-
ing the heater output.
The setpoint may be adjusted by doing the following:
1. Press the up or down arrow until the lower
display shows the desired setpoint. The lower
display will blink, showing the value has not
been set yet.
2. Press the set button. The lower display will stop
blinking, showing the new value has been set.
High Temperature Alarm Setpoint
The 4838 Reactor Controller also has a HighTem-
perature Alarm built into it. When the temperature
exceeds this limit, it will pop the High Limit Reset,
preventing power from going to the heater. The
HighTemperature Alarm setpoint may be adjusted
by doing the following:
1. Press the circular arrow key three times. The up-
per display will read AL1H and the lower display
will read the HighTemperature Alarm setpoint
(usually 375 °C).
2. Use the up or down arrow to adjust this to the
desired setpoint.
3. Press the up or down arrow until the lower
display shows the desired setpoint. The lower
display will blink, showing the value has not
been set yet.
4. Press the set button. The lower display will stop
blinking, showing the new value has been set.
5. Pressing the set button again will return the dis-
play to the main screen.
PID groups
a. The primary temperature controller contains
4 groups of PID parameters (PID0, PID1, PID2
and PID3), which can be used to store up to four
different sets of PID parameters. Each group is
identified by the SV used during the autotuning
cycle.
b. The parameter displayed is the group in use
with exception of PID4. When PID4 is set, the PID
parameters will automatically switch between
PID groups 0, 1, 2 and PID group 3, depending
on which group’s SV best matches the current
temperature (PV).

4838 Reactor Controller
11
c. All of PID parameters in the group can be ob-
tained from auto-tuning or they can be set
manually. When manually entering PID values
into a particular group, the SV for that group can
be manually entered as well.
Autotuning
1. Fill the vessel with an amount of liquid which
well represents the intended process.
Caution!
Refer to Manual 230M for safety information
on the heating of liquids in Reactors
and Pressure Vessels.
2. If you wish to autotune at different temperatures
using the four available PID groups proceed with
step 3, otherwise skip to step 4.
3. Press the set key once followed by the return key
(circular arrow) twice. [PID0] will be displayed
on the screen in the top display. Use the up and
down arrow keys to change between PID groups
0, 1, 2 and 3. Press the set key to solidify the
change. Press the set key again to return to the
main screen.
4. Heat the system to the desired temperature us-
ing set point control on the primary temperature
controller. Let the temperature come to steady
state which will typically occur 15 to 30 minutes
after reaching the desired set point depending
on the size of the reactor.
5. On the main screen of the controller, press the
set key.The screen will show [AT] on the top
display and [OFF] on the bottom display. Press
the up arrow to change the lower display to
[ON].The display will blink, press set to solidify
the change. Press set again to return to the main
screen.
6. As the Autotune starts, the LED indicator under
AT will blink, and Out 1 will fully engage at-
tempting to heat the reactor 100% power.This
will continue for a while, and the controller
will go through a few cycles where it turns the
power on at 100% and turns it off to see how the
temperature responds.
7. A typical Autotune time is half an hour for liquid
water systems, but it may take longer depending
on the process. When the process is complete,
the AT light will stop flashing, and the tempera-
ture will settle on the set point.
Temperature Profiles - Ramp and Soak
The 4838 Controller has a programming feature
which allows more flexibility when compared to set
point control. Rather than controlling temperature
to a single set point, a ramp and soak program may
be entered to control various soak times, ramp rates
and set points. Within the programming mode there
are eight patterns available with each pattern hav-
ing up to eight steps which can be programmed.
Patterns can be set to repeat and they can be linked
to other patterns (or the same pattern which allows
for infinite program cycles).This allows for up to 64
unique steps and thousands of possible program
configurations.
To input a ramp and soak:
1. First set the controller’s Run/Stop [R-S] pa-
rameter to Stop [STOP].This will prevent the
program from automatically starting after the
program has been entered.You can do this by
pressing the return key once and use the arrow
keys to change the setting to “stop” and press
the set key to solidify the change.
2. To enable the ramp and soak control mode, hold
the set key for approximately three seconds.The
upper display will change to indicate the Input
[INPT] parameter, and the lower display will
indicate the temperature sensor type.
3. Press the return key until the upper display
indicates the control mode parameter [CRTL]
and the lower display indicates the control
method (default is PID [PID]). Use the arrows
to change this value to the program [PROG]
setting.The display will blink, and pressing the
set key will solidify the change.
4. Press the return key once.The upper display will
indicate the pattern [PATN] parameter and the
lower display will show the pattern number.The
pattern parameter defines which pattern param-
eters are being viewed in steps 5 - 10. Setting the
pattern parameter to off [OFF] allows you to
skip the proceeding ramp/soak parameters. Use
the arrow keys to change the pattern number
and press the set key to solidify the change.
5. Press the return key once.The upper display will
read [SP00], where the “00” represents the
pattern and step number, respectively.The lower
display will indicate the set point for indicated
step.The set point can be adjusted using the
arrow keys then press the set key to solidify the
change.

4838 Reactor Controller
12
Note: The first SP_O used must be a higher
temperature than the current temperature
(PV) or the program will not execute properly.
6. Press the return key once.The upper display will
read [TI00], where the “00” represents the
pattern number and the step number, respec-
tively.The lower display will show the time to
execute the current set point in “hh:mm” format.
The time setting can be changed by using the
arrow keys then press the set key to solidify the
change.
7. Repeat steps 4 and 5 for “SP01” through “SP07”
and “tI01” through “tI07” as required. Once you
have entered all the steps you want, you can
leave the remaining “SP” and “tI” variables at
zero and press the return key to advance.
8. Press the return key to display [PSY0] on the
upper display, where “0” represents the current
pattern number.This parameter determines the
last step to execute in the pattern. For example,
if PSy0 has a value of 3, Steps SP00 through
SP03 will execute. Use the arrow keys to change
the setting and press the set key to solidify the
change.
9. Press the return key to display [CYC0], where
“0” represents the pattern number.This pa-
rameter defines how many times you want the
indicated pattern to repeat. If you would like the
pattern to only execute once, set this value to
zero. Use the arrow keys to change the setting
and press the set key to solidify the change.
10. Press the return key to display [LIN0], where
“0” represents the pattern number.This pa-
rameter allows you to link the indicated pat-
tern another. If you would like more than seven
separate steps in the process, set this to the next
pattern number you wish to link to. Use the ar-
row keys to change the setting and press the set
key to solidify the change.
11. Press set to return to the main screen. Note
that the lower display of the main screen has
changed to show the program step.
Note: The program will attempt to hold the
temperature at the set point determined by
the last step executed. So, if you wish for the
reactor cool to room temperature once the
program has finished, the last executed step
must have a set point consistent with room
temperature and the time for the last step
can be set to 00:00.
Engaging a Program
1. From the main screen, press the return key two
times to display [PTRN] on the upper display.
The lower display will indicate the pattern at
which you wish to execute.
2. Press the return key until the run/stop parameter
[R-S] is on the upper display.The lower display
will indicate the setting of the run/stop parame-
ter. Change this value to [RUN] in order to start
the program determined in step 1. Press set to
return to the main screen.
If you wish to stop the program completely, you
may change this value to [STOP]. Changing
the run/stop mode back to stop will restart the
program from the beginning.
If you wish to stop the program and continue
controlling the temperature at the current set
point, you may change this value to program
stop [PSTP]. Changing back to run mode from
a program stop will restart the program from the
beginning.
If you wish to hold the program at the current
temperature, you may change this to program
hold [PHOD]. Changing back to run mode from
a program hold will continue the program from
its current step.
3. The main screen will now show the current set
point on the lower display. Pressing the arrows
will allow you to change between: [P-ST] to
display the current pattern and step, [R-TC] to
display the remaining time in the current pat-
tern step, or [SP] to display the set point for the
current pattern step. Press set will solidify this
display change.

4838 Reactor Controller
13
A sample program to heat to 200 °C as fast a pos-
sible, hold for 2-hrs, and come back down as quickly
as possible:
Variable Value Meaning
ptrn 00 Pattern 0
SP00 200 Setpoint of 200 °C (first step is
a soak by default)
tI00 00:00 Move setpoint to 200 °C im-
mediately
SP01 200 Setpoint of 200 °C
tI01 01:00 Ramp from 200°C to 200 °C
over 1-hrs *
SP02 200 Setpoint of 200 °C
tI02 02:00 Ramp from 200C to 200 °C over
2-hrs **
SP03 25 Setpoint of 25 °C
tI03 00:00 Ramp to setpoint immediate-
ly***
SP04 25 Setpoint of 25 °C
tI04 00:00
SP05 25 Setpoint of 25 °C
tI05 00:00
SP06 25 Setpoint of 25 °C
tI06 00:00
SP07 25 Setpoint of 25 °C
tI07 00:00
PSy0 3 Execute steps 0-3 only****
CyC0 0 Do not re-cycle program
Lin0 off Do not execute another pro-
gram upon completion of this
program
* The physical system will take some time to go from
room temp to 200 °C. Step 01 is presented as a “heat
up” step. The time value in this step should be ad-
justed after the first run is complete and the operator
knows the expected heat up time.
** It is useful to keep this step 02 separate from step
01 so you can adjust step 01 to match the heat up
time.
***The time is zero, making this a step function in-
stead of a ramp.
**** Steps 4-7 are not executed here.
Appendix: sample programs
A sample program to ramp from 25 °C to 250 °C in
2-hrs:
Variable Value Meaning
ptrn 00 Pattern 0
SP00 25 Setpoint of 25 ºC (first step is a
soak by default)
tI00 00:01 Hold for 1-min
SP01 250 Setpoint of 250 °C
tI01 02:00 Ramp to setpoint in 2 hrs
SP02 250 Setpoint of 250 °C
tI02 00:40 Ramp to setpoint in 40-min*
SP03 25 Setpoint of 250 °C
tI03 00:00 Ramp to setpoint immediately**
SP04 25 Setpoint of 25 °C
tI04 00:00
SP05 25 Setpoint of 25 °C
tI05 00:00
SP06 25 Setpoint of 25 °C
tI06 00:00
SP07 25 Setpoint of 25 °C
tI07 00:00
PSy0 3 Execute steps 0-3 only***
CyC0 0 Do not re-cycle program
Lin0 off Do not execute another program
upon completion
* The beginning and final setpoint are equal, making
this a soak step.
**The time is zero, making this a step function in-
stead of a ramp.
*** Steps 4-7 are not executed here.
****The SP_0 vaue must be higher than the initial
temperature (PV) of the reactor or the program will
not initiate correctly.

4838 Reactor Controller
14
Pressure Display Module (PDM)
PRESSURE
When this optional module is present, the left dis-
play in red shows the pressure, and the right hand
display in green shows the Pressure Alarm setpoint.
If the reactor pressure exceeds this setpoint, the
pressure module will trip the High Limit Alarm, cut-
ting power to the heater.
This module provides a digital read out for continu-
ously monitoring the pressure within the reactor,
plus a backup safety feature which will terminate
power to the heater if a preset maximum is reached.
Pressure is displayed with a 1 psi resolution and a
1% FS accuracy. The safety cut-out feature offers
excellent protection against accidental over-pressure
by allowing the user to set a maximum pressure
which, if reached, will activate the high limit relay
and turn off the heater immediately.
The signal for the pressure display is generated by
a transducer in a stainless steel housing mounted
on the reactor. The transducer must not be heated
above 120 °C; an elevated temperature can caused
the accuracy of the transducer to suffer. A water
cooling sleeve attached to the transducer mounting
body can be used to keep the transducer below this
limit when operating the reactor at higher tempera-
tures.
For applications involving reactants corrosive to
stainless steel, the transducer body can be replaced
with an isolator of special alloys which will keep the
reactants away from the transducer. Users should
consult with the Technical Support before pur-
chasing one of these.
The Pressure Alarm setpoint may be adjusted by do-
ing the following:
1. Press the up or down arrow until the lower
display shows the desired setpoint. The lower
display will blink, showing the value has not
been set yet.
2. Press the set button. The lower display will stop
blinking, showing the new value has been set.
When ordering a pressure display module sepa-
rately or installed in any controller, always
specify the reactor on which the transducer will be
installed so that the proper mounting hardware can
be furnished.
Note: if the pressure transducer is not attached
to the 4838 Controller, the High Limit Reset
may trip or show a fixed but incorrect value.
We recommend always operating with the
transducer attached.
High-Temp Cut-Off Module (HTM)
TEMPERATURE
This module provides a redundant high tempera-
ture safety cut-off which will shut down the reactor
heater if an unusual malfunction should develop in
the primary control system. It is a completely inde-
pendent safety backup system, operating in addition
to the high-limit control built into each tempera-
ture controller. It has its own thermocouple, digital
display and wiring, and can be preset to shut down
the heater at any desired temperature.

4838 Reactor Controller
15
If the secondary temperature (PV) exceeds the alarm
setpoint (SV), the alarm indicator on this display will
illuminate and the High Limit breaker will trip, inter-
rupting power to the heater.
The HighTemp Cut-Off Alarm setpoint may be ad-
justed by doing the following:
1. Press the up or down arrow until the lower
display shows the desired setpoint. The lower
display will blink, showing the value has not
been set yet.
2. Press the set button. The lower display will stop
blinking, showing the new value has been set.
This secondary temperature module does not con-
trol the heater. It is used as an alarm only.
When ordering this option separately or installed in
the 4838 Controller, always specify the reactor
with which it will be used so that a thermocouple of
the proper style and length can be furnished.
External Heater Temperature Limit Control
Module (ETLM)
TEMPERATURE
ETLM
This module should be considered in systems with
large thermal lags or long dead times such as gas
phase reactions or other systems where tempera-
ture control is difficult.
This configuration is similar to the HighTempera-
ture Cut Off Module (HTM), but the display will now
turn off the heater if it exceeds a pre-set adjustable
setpoint. This non-latching setpoint will establish a
maximum wall temperature, and combined with the
main temperature control module will help suppress
overshoot in difficult to control processes.
As an added safety feature, there is also a second-
ary alarm which will trip the High Limit Reset when
breached. This secondary alarm provides a redun-
dant high temperature safety cut-off which will shut
down the reactor heater if an unusual malfunction
should develop in the primary control system. It is
a completely independent safety backup system,
operating in addition to the high limit control built
into each temperature controller. It has its own
thermocouple, digital display and wiring, and can be
preset to shut down the heater at any desired tem-
perature.
To set the primary (non-latching) temperature limit,
press the up or down arrow on the display. The set-
point value on the right will flash. Press the set but-
ton to solidify this display and complete the change.
If the heater temperature exceeds the ETLM setpoint
(non-latching), the output to the heater will be inter-
rupted. This will not trip the High Limit Reset, and
when the heater temperature falls back below the
primary setpoint, it will allow power to flow to the
heater again.
To set the secondary (latching) temperature limit,
press the circular arrow key three times. The left-
hand display will read ALIH and the right-hand
display will read the secondary temperature limit
setpoint (usually 375 °C). Press the up or down ar-
row on the display. The setpoint value on the right
will flash. Press the set button to solidify this dis-
play and complete the change.
When ordering this option separately or installed in
the 4838 Controller, always specify the reactor
with which it will be used so that a thermocouple of
the proper style and length can be furnished.

4838 Reactor Controller
16
Communication with PC
The 4838 Controller is provided with RS-485 port
(labeled comm) and may be connected to a USB
port on a PC with optional A1925E4 communication
cable.
Quick Start Instructions for Connecting with PC
1. Put the 552M CD into the CD-ROM.
2. Connect the A1925E4 communication cable
between the comm port on the back of the 4838
Controller and an open USB slot on the PC.
3. The PC should open an "Install Hardware" wizard
automatically when the cable is connected to the
USB slot. If it does not, go to the Control Panel
and select "Add Hardware" to start the wizard.
4. When prompted, check the box to search re-
movable media for the proper driver. The wiz-
ard should find the driver on the 552M CD and
install the USB driver. It may prompt that the
driver has not been validated; select "continue
anyway" to continue the installation. After this
it may repeat the installation process for the RS-
485 converter.
5. Copy the controller software to the PC. The soft-
ware is located on the CD at: "software ___\ Com.
exe”.
6. Once copied to the PC, open the ___ Com.exe
file. No installation is necessary.
7. At the main ___ Com program screen, select
"protocol >> set PC". Ensure that the following
values are set:
Baud: 9600
Data length: 8
Parity: even
Stop bit: 1
ASCII: RTU
Click OK to return to the main screen.
8. At the main screen, select "Program >> Monitor".
The Monitor screen will come up. There will be
a generic icon on the left, and four mini screens
on the right. Each mini screen can be used to
connect to a different module on the 4838 Con-
troller.
9. In the first mini screen, select 1 for the Address,
and click Connect. It should connect to the
PrimaryTemperature module on the 4838 Con-
troller, and the bottom half of the screen should
show parameters for the controller.These may
be modified here. Of most interest will be the
"Input >> SV" value, which is the setpoint for
temperature. Also, the "Alarm >> Alarm 3" value
will show the High Limit alarm for this module.
10. Any other modules on the 4838 Controller may
be accessed through the remaining available
mini screens. A pressure display module will
typically be address 3 and an HTM/ETLM will be
adress 4.

4838 Reactor Controller
17
Datalogging and Charting
The 4838 Controller comes equipped with a charting
and datalogging program. This program cannot be
run simultaneously with the control program, but
once the user is satisfied that the controller is set,
the control program may be closed, allowing the
charting and datalogging program to run. The mod-
ules on the 4838 may still be modified manually at
the physical panel during datalogging and charting.
1. Open the ___ Com.exe file. No installation is
necessary.
2. At the main program screen, select "protocol >>
set PC" (if you have already done previously, you
may skip this step). Ensure that the following
values are set:
Baud: 9600
Data length: 8
Parity: even
Stop bit: 1
ASCII: RTU
Click OK to return to the main screen.
3. At the main screen, select "Program >> Record-
er". The Recorder screen will come up.
4. Select the proper address for the Devices you
wish to chart. The primary temperature has ad-
dress 1. A pressure display module will typically
use address 3 and an HTM/ETLM will use ad-
dress 4.
5. Click the Save button and save a REC
file to an appropriate place on the PC.
When the chart is generated, it will
write to this file.
6. When you return to the main Record-
er screen, notice that the Save button
is depressed. Hit the Start button to
begin recording.
7. The chart will show the process values of each
module represented. As the values change, the
chart will automatically scale to show the values.
8. When you wish to stop recording, click the stop
button. The chart has already been
saved in the REC file created in step 5.
You may view the chart by clicking the
recorder button.
9. You can convert the file to aTXT file for export to
a spreadsheet as well.
Converting a Chart File to TXT
Once a chart REC file has been created, you can con-
vert it to aTXT file for export into a spreadsheet.
1. Insert the 552M CD into the CD-ROM. Locate the
conversion file at “ \software\convert.exe”. Copy
it to the PC.
2. Open the convert.exe file. No installation is
necessary.
3. Click the "CONVERT" button. Locate the REC file
to be converted, and click "Open".
4. The conversion program will create a newTXT
file in the same location as the REC file with the
name "CONVFILE.TXT".

4838 Reactor Controller
18
4838 Factory Defaults
Navigating the Menu System / Factory
Default Settings
There are three broad categories of functions in the
4838 Controller modules. They are Regulation, Op-
eration, and Initial Settings. From the main screen,
Regulation mode is accessed by pressing the set
button. The Initial Setting mode is accessed by
holding the set button for three seconds. Operation
mode is accessed by pressing the circular arrow.
In each mode, you can cycle through the variables
by pressing the circular arrow. To change a value,
use the up or down arrow, which causes the value
to flash. Then press the set button to solidify the
choice. Return to the main screen by pressing set
again.
Keys command:
1. Press “SET” to select
2. Press return key move to next operation mode
3. Up/Down arrow keys to adjust value or select
type
Primary Temperature Module
Press return key and release
Operation
Mode
Select
type/value Comment
r-S Run Run/Stop
SP 0** Decimal point position
AL1H 375 Upper alarm setting
LoC OFF Lock mode (lock all keys
or only up/down arrow
able to use)
Out1 - (read-only) Heater output %
** If using a type-J or type-K thermocouple, SP = 0
If using an RTD, SP = 1
Press and hold down “SET” for 5-sec
Operation
Mode
Select
type/value Comment
InPt J** Input type
tPUn C Temperature unit
tP-H 800** Upper-limit range
tP-L 0 Lower-limit temperature
range
CTRL PID Control mode (ON/OFF,
MANUAL, PID and PID
PROG)
S-HC HEAT Output 1 is Heating
ALA1 6 Alarm operates when PV
value is higher than AL1H
setting or PV value is
lower than AL1L setting
ALA2 0 Alarm 2 is disabled
ALA3 0 Alarm 3 is disabled
SALA OFF System alarm
CoSH ON Communication write
function that able to use
set point from software
C-Sl RTU Format type
C-no 1 Communication address
bPS 9600 Communication baud
rate
Len 8 Data length setting
PrtY Even Parity bit setting
StoP 1 Stop bit setting
** If using a type-J thermocouple, InPt = J, tP-H = 800
If using a type-K thermocouple, InPt = K, tP-H = 800
If using an RTD, InPt = Pt, tP-H = 600
Press “SET” and release
Operation
Mode
Select
type/value Comment
At OFF AutoTuning ON/OFF
PID0 0 The 0th PID Parameter
SV 0 The 0th SV
P0 11. 8 Proportional control
I0 375 Integral control
D0 93 Derivative control
IoF0 0 Integral value offset
HtPd 5 Heat cycle control
CoEF 1 1 & 2 value output group
during dual loop output
control
tPoF 0 Inaccuracy adjustment

4838 Reactor Controller
19
Pressure Module
Press return key and release
Operation
Mode
Select
type/value Comment
r-S Run Run/Stop
SP To be deter-
mined**
Decimal point position
AL1H 0 Upper-limit alarm 1
LoC OFF Lock mode (lock all keys or
only up/down arrow able
to use)
** If units are psi, SP = 0
If units are Bar, SP = 1
If units are MPa, SP = 2
Press and hold down “SET” for 5-sec
Operation
Mode
Select
type/value Comment
InPt V5 Input type (V5 = 0-5V, V10
= 0-10V, nA0 = 0-20mA,
nA4 = 4-20mA, nV =0-
50mV)
tP-H Determined
by transduc-
er**
Upper-limit pressure range
tP-L 0 Lower-limit pressure range
CTRL ON/OFF Control mode (ON/OFF,
MANUAL, PID and PID-
PROG)
S-HC Heat Heat/Cool control
ALA1 2 Alarm operates when PV
value is higher than SV
Value + ALH setting
SALA OFF System alarm
CoSH ON Communication write
function that able to use
set point from software
C-Sl RTU Format type
C-no 3 Communication address
bPS 9600 Communication baud rate
Len 8 Data length setting
PrtY Even Parity bit setting
StoP 1 Stop bit setting
** Set according to the following:
Transducer
range - psi
tP-H for
psi
tP-H for
Bar
tP-H for
MPa
200 200 13.79 1.38
300 300 20.68 2.07
500 500 34.47 3.45
1000 1000 68.95 6.89
2000 2000 137.9 13.79
3000 3000 206.8 20.68
5000 5000 344.7 34.47
7500 7500 517.1 51.71
Press “SET” and release
Operation
Mode
Select
type/value Comment
HtS 0 Heating hysteresis setting
tPoF 0 Temperature correction

4838 Reactor Controller
20
HTM / ETLM Module
Press return key and release
Operation
Mode
Select
type/value Comment
r-S Run Run/Stop
SP 0** Decimal point position
AL1H 375*** Upper-limit alarm 1
LoC OFF Lock mode (lock all keys or
only up/down arrow able
to use)
Out1 - (read-only) Heater Output %
** If using a type-J or type-K thermocouple, SP = 0
If using an RTD, SP = 1
***If using an HTM, AL1H = 0
If using an ETLM, AL1H = 375
Press and hold down “SET” for 5-sec
Operation
Mode
Select
type/value Comment
InPt J** Input type
tPUn C Temperature unit
tP-H 800** Upper-limit temperature
range
tP-L 0 Lower-limit temperature
range
CTRL ON/OFF Control mode (ON/OFF,
MANUAL, PID and PID
PROG)
S-HC Heat Heat/Cool control
ALA1 6*** Alarm operates when PV
value is higher than AL1H
value
SALA OFF System alarm
CoSH ON Communication write
function that able to use
set point from software
C-Sl RTU Format type
C-no 4 Communication address
bPS 9600 Communication baud rate
LEn 8 Data length setting
PrtY Even Parity bit setting
StoP 1 Stop bit setting
** If using a type-J thermocouple, InPt = J, tP-H = 800
If using a type-K thermocouple, InPt = K, tP-H = 800
If using an RTD, InPt = Pt, tP-H = 600
***If using an HTM, ALA1 = 2
If using an ETLM, ALA1 = 6
Press “SET” and release
Operation
Mode
Select
type/value Comment
HtS 0 Heating hysteresis setting
tPoF 0 Inaccuracy adjustment