Instruction manual

5–6 Ramp and Dwell

Example 1: Temperature cycling chamber

A chamber is used to test the temperature cycling effect on

personal computers. An external cycle timer is used to control

the event input for switching the set point. The products under

test are required to stay at 60°C for 1 hour and -10°C for 30

minutes. The transition interval between the high and low

temperatures is required to be 5 minutes. Make the following

setup:

EIFN = SP.P2

A1FN = TIMR

OUT1 = REVR, relay output

OUT2 = COOL, 4–20mA output

SPMD = MINR

IN1U = °C

DP1 = 1-DP

The circuit diagram and its temperature profile are shown below:

The TEC-9300 provides a 4–20mA signal to control the speed

of the inverter. SP.P2 is chosen for EIFN in order to create a dual

PID control. You can perform auto-tuning twice at SP1 and SP2

for the initial setup for the dual PID values. Refer to sections

3-19 and 4-3.

Example 2: Programmable bread baking oven

Bread is baked in batches. A ramp is incorporated to control

the thermal gradient to suit for making the bread. A dwell timer is

used to shut off the oven power and announce this to the baker.

The system is configured as shown in the following diagram.

Order a form B relay for alarm 1. Push the ON switch to start

a batch. The temperature will rise with a ramp rate determined by

the RAMP value. The bread is baked with the set point tempera-

ture for a predetermined amount of time which is set in the TIME

value, and then the power is shut off. The temperature profile is

shown in the following figure.

Terminal

, use

Form B Relay