PROCESS DYNAMIC & CONTROL

Temperature control report

Name: Omar Mohamed Mohamed Mamdouh

I
Contents
Abstract ............................................................................................................................................ I
1. Introduction ............................................................................................................................. 1
1.2. Equipment description and function ................................................................................ 1
1.3. Commissioning................................................................................................................. 2
1.4. Shutting down .................................................................................................................. 2
2. Procedures ............................................................................................................................... 3
2.1. Control Loop ........................................................................................................................ 3
2.2. Continuous control: .......................................................................................................... 3
3. Experimental results ................................................................................................................ 5
4. Discussion and conclusion....................................................................................................... 7
5. Bibliography ............................................................................................................................ 8

II
 1. Introduction

The RT 040 temperature control model represents a typical loop control system, as is standard
and widespread in engineering. The actual loop is a metal bar inserted into a heat-insulating
cladding tube. The end of the bar is heated by an electric heater. Along the axis of the bar, i.e. in
the direction of dispersion of the heat, are three equally spaced temperature sensors, which can
be used as signal transmitters for a controller. As a disturbance, a small electric fan can be
connected, which dissipates part of the heat output and withdraws it from the bar. The model
must be supplemented by a separate external controller to create a complete control loop. It
communicates with the peripheral equipment (e.g. a PC) via a USB interface. The most suitable
control and regulation program is the associated software RT 010- RT 060.

1.2. Equipment description and function

The RT 040 temperature control model is used as a simple loop for a controller. It does not
include a controller itself; all control processes must be run externally. The model communicates
with external devices via a USB interface, for which it has a plug-in connection on the rear. The
active actuator on this model is an electrically operated Peltier element (2), which can be used
for either heating or cooling. These two options open up the possibility of three-point control.
The element is fitted between a dissipater (1) and a heat conducting bar (3). For heating, it is

1
supplied with an electrical voltage of appropriate polarity, such that the side facing the bar is
cooled. As an additional disturbance, an electrically powered fan (1) is fitted before the dissipater
on the side facing away from the bar, which can optionally be connected. To allow dosing of the
disturbance, actuation is cyclic, with a changing pulse/pause ratio. Equally spaced PTC resistors
(5) are inserted into the heat conducting bar to record the temperature. T1 - Start of bar (close to
heater) T2 - Centre of bar T3 - End of bar Depending on the sensor position, the resulting loop
behavior is different, e.g.: T1 - PT1 behavior T2 - Noticeable idle time behavior to create
uniform thermal conditions, the heat conducting bar is embedded in an insulated cladding tube
(3). As the temperature is measured by sensors, the control thermometer (4) is only intended to
provide a guide to the temperature in the center of the bar (plausibility).

1.3. Commissioning

Connect the model to the mains using the connecting socket on the rear.
Using the USB port on the rear of the model, connect it to an external controller (e.g. PC).
Switch on the model at the master switch (7).
Switch on the heater (4). The model is now ready for use.

1.4. Shutting down

To shut down, the model only needs to be switched off at the master switch. The model should
be disconnected from the mains if it will not be used for a long period of time. The unit is
maintenance free and does not require any additional servicing.

2
 2. Procedures

2.1. Control Loop

a) Determination of loop type:

The loop type is determined by way of a step in the reference variable and observation of
the resulting transient response.

Select Manual operating mode and set the manual regulation ratio to y = + 100 %
(heating).

Now wait until the temperatures have reached a steady state.

2.2. Continuous control:

a) P control:

In the following section, the influence of a pure P component on the control of the reference
variable is initially observed.

Select Continuous control operating mode.

In System diagram, select measuring point T3Set parameters:

K= 10

Tn= 0 s

Tv= 0 s

W1= 25 C

Perform step in reference variable by selecting W 2= 35 C, wait for steady state.

3
b) PID control of reference variable:

The following section is designed to demonstrate how an additional I and D component

Select Continuous control operating mode.

In System diagram, select measuring point T3

Set parameters:

Kp= 1.1

Tn= 750 s

Tv= 75 s

W1= 20 C

Perform step in reference variable by selecting W 2= 35 C, wait for steady state.

4
 3. Experimental results
The system was configured at first to be 0% for the disturbance response (Z) and regression ratio
(Y) = 75%.

According to this configuration, the temperature was supposed to be 32.2oC

5
When increasing the regression ratio (Y) to 100% at the same disturbance response Z = 0%

By increasing (Y), the temperature was increased to 44.1oC

Then, the regression ratio was decreased (Y) to 20% at the same disturbance response (Z) = 0%

The temperature also was increased in spite of decreasing (Y) to be 44.9oC

6
4. Discussion and conclusion

7
 5. Bibliography
G.U.N.T. - Equipment for engineering education -. (2017). Unhas.ac.id. Retrieved 4 May 2017,
from http://www.unhas.ac.id/rhiza/arsip/kuliah/Sistem-dan-Tekn-Kendali-
Proses/GUNT%20Catalog/html/p3406.htm