Parr Instrument 4838, Operating Instructions Manual

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 fi rst 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 fi nal 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.