Temperature Accessories
Alarms are used to monitor temperature, flow, level, and pressure in processes.
Alarms are used to monitor temperature, flow, level, and pressure in processes. When the process conditions exceed limits set in the alarm unit, a signal is sent to activate horns, lights, and control room alarms so that corrective action can be taken.
Temperature Controllers
Universal electric controllers are used to control process variables such as flow, level, pressure, and temperature in single or dual-loop operations. The controllers can take in 4-20mA analog input signals and RTD’s, or thermocouples directly. The controller compares the input to a setpoint. As the input deviates from the setpoint, the controller sends an analog or digital signal to a device such as a control valve that operates to bring the measured unit back to the setpoint. Many controllers have RS-485 interface so they can be used with personal computers or larger systems.
Temperature Recorders
Industrial recorders provide data acquisition and recording by accepting analog voltage, RTD and other inputs which represent process variable conditions such as flow, level, pressure, and temperature.
The results are printed on a paper chart or they are displayed on an LCD screen with paperless recorders. Recorders acan also provide alarm relay outputs if inputs exceed user selected set points. The recorders can also retransmit a process variable via an analog 4-20mA output, and can perform totalizing functions. Some recorders can be used as controllers to provide outputs to control valves and other devices when process inputs differ from set points.
Some recorders can also be built with Ethernet connectivity with support for common protocols to provide networking to a lare area network, or the world wide web. For date export, a SD card or USB flash storage capability is available on some models.
Temperature Switches
Temperature switches are devices which normally use a temperature sensor like an RTD or thermocouple to measure the temperature of gases, liquids, and steam in pipes, tanks, and other vessels.
The measurement is compared to a setpoint in the switch mechanism or electronics which then sends an electronic or electric output when the temperature deviates from the setpoint more than a chosen amount.
Outputs are often used as alarms, but can also be used to operate other devices such as on/off control valves used to help control the temperature in a building, pipe, tank, or other vessel.
