Overview of temperature controller
A temperature controller is an equipment that keeps the required temperature at a specific value.
For example home thermostat, a water heater USES a thermostat to regulate water temperature and maintain a controlled temperature. The temperature controller is also used in the oven. Once the oven temperature is set, the control system monitors the actual temperature in the oven. If the temperature drops below the set temperature, an activation heating signal is sent to reset the temperature to the set value. Thermostats are also used in refrigerators. If the temperature is too high, the control unit will take measures to lower the temperature.
General temperature controller application
Industrial temperature controllers work in a similar way to typical home applications. Basic temperature controllers control industrial or laboratory heating and cooling processes. In typical applications, sensors measure the actual temperature. Constantly compare the recorded temperature to the value set by the user. If the actual temperature deviates from the set value, the controller generates an output signal that activates other temperature control devices, such as heating elements and cooling components, to return the temperature to the set value.
Temperature controllers are used in various industries to control manufacturing processes and procedures. Typical applications of industrial temperature controllers are plastic extruders and injection molding machines, thermoforming machines, packaging machines, food processing, food storage and blood Banks. The following is an overview of common temperature control applications in the industry.
Temperature controllers are used for heat treatment applications in ovens, ovens, ceramic ovens, boilers and heat exchangers.
In the packaging field, machines equipped with seals, gluers, hot melt functions, shrink channels or labeling must operate at specified temperatures and processing times. The temperature controller precisely adjusts these processes to ensure high yields.
Temperature control in the plastics industry is common in portable coolers, hoppers, dryers, molding and extrusion equipment. The extruding system USES a temperature controller to closely monitor and control the temperature at key points in plastic manufacturing.
To improve the accuracy of temperature control, temperature controllers are used in healthcare. Typical equipment using a temperature controller includes laboratory and test equipment, autoclave, incubator, refrigerator, crystal growth room and test room. These samples are required to be stored within certain temperature parameters.
Food & Beverage
Common applications of food processing include temperature control, including brewing, mixing, sterilization, cooking and baking. The temperature controller adjusts the temperature and processing time to ensure optimal performance.
Parts of a Temperature Controller
All controllers have something in common. First, the controller has input. Enter the variables used to measure the process to be controlled. For the temperature controller, the variable measured is temperature.
Temperature controllers have different types of inputs. The type of input sensor and the signal required may vary depending on the type of process to be controlled. Common input sensors include thermocouples and RTD, as well as linear inputs such as mV and mA. Typical standardized thermocouple types include J, K, T, R, S, B, and L types.
The controller can also be configured to accept RTD temperature sensor input. A typical resistance thermometer is 100 Ω platinum sensors.
Controls typically have integrated capabilities to detect failure or absence of input sensors. This is called sensor damage detection. Failure to identify this fault condition could seriously damage the controlled equipment. With this function, the controller can stop the process immediately if the sensor state is detected.
All controllers have outputs in addition to inputs. Each output can be used for different purposes, such as b. control the process (such as turning on a heating or cooling source), triggering an alarm, or retransmitting the process value to a programmable logic controller (PLC) or logger. Can the
Conventional outputs provided by the temperature controller include relay outputs, solid state relay (SSR) drivers, three-terminal bidirectional thyristor switches, and linear analog outputs. Relay output is usually a single-pole SPDT (double-throw) relay with a dc coil. The controller supplies current to the relay coil and isolates the contacts. This allows the contact to control the external voltage source to power the larger heated contactor coil. It is important to note that the current carrying capacity of relay contacts is usually less than 2A. The contacts can be used to control the heating contactor with A power of 10 to 20 A for the heating strip or heating element.
Another output is the SSR driver. The SSR driver output is a logical output used to turn on or off a solid-state relay. Most solid-state relays require direct current from 3 to 32 VDC to connect. The 10 V on signal of the universal SSR driver controls three solid state relays.
Controller alarm comparison
The temperature controller has several other parameters, one of which is the set value. A set value is basically a set value set by the operator to keep the controller stable. For example, if the temperature is set to 30°C, the controller will try to keep the temperature at that value.
The other parameter is the alarm value. Used to indicate that a process has reached a state. There are different types of alerts. For example, a high alarm may indicate that the temperature is higher than the set value. A low alarm also indicates that the temperature has dropped below the set point.
For example, in a temperature control system, a highly fixed alarm prevents thermal damage to the equipment by turning off the heat source when the temperature exceeds the set value. On the other hand, if the equipment is likely to be damaged by cryogenic freezing, a low set alarm can be set.