Thermocouple Transmitter, Ethernet & 4-20 mA Outputs

The Laureate thermocouple transmitter provides a linearized, highly accurate, stable and repeatable transmitter output for thermocouple types J, K, T, E, N, R or S. The thermocouple type and temperature range, specified in °C or °F, are user-selectable. The temperature range can be as wide as the entire span of the thermocouple type, or as narrow as 150 counts (such as 15.0°), limited only by considerations of electrical noise and digital filtering time constants.

All ranges for all thermocouple types are digitally calibrated at the factory, with calibration factors stored in EEPROM on the signal conditioner board. This allows temperatures sensors and signal conditioner boards to be changed in the field without recalibrating the meter. For cold junction compensation (CJC), an external transistor is mounted adjacent to the thermocouple input to measure ambient termperature. That transistor is calibrated as a system with the signal conditioner board.

Fast read rate at up to 50 or 60 conversions per second while integrating the signal over a full power line cycle is provided by Concurrent Slope (Pat 5,262,780) analog-to-digital conversion. High read rate is ideal for peak or valley capture and for real-time computer interface and control.

Standard features of Laureate LTE transmitters include:

• Ethernet I/O, isolated. The supported protocols are Modbus RTU and ASCII, which are tunneled via Modbus TCP. Note that RS232 or RS485 data I/O is provided by Laurel's LT Series transmitters.
• 4-20 mA, 0-20 mA or 0-10V analog transmitter output, isolated, jumper-selectable and user scalable. All selections provide 16-bit (0.0015%) resolution of output span and 0.02% output accuracy of a reading from -99,999 to +99,999 counts that is also transmitted digitally. Output isolation from signal and power grounds eliminates potential ground loop problems. The supply can drive 20 mA into a 500 ohm (or lower) load for 10V compliance, or 10V into a 5K ohm (or higher) load for 2 mA compliance.
• Dual solid state relays, isolated. Available for local alarm or control. Rated 120 mA at 130 Vac or 180 Vdc.
• Universal 85-264 Vac power. Low-voltage 10-48 Vdc or 12-32 Vac power is optional.

Node discovery and configuration of Laureate Ethernet transmitters are easily achieved with Laurel's Windows based Instrument Setup Software. Additional features are provided by Laurel's Windows based Node Manager Software, such as the ability to send emails or test messages either periodically or in the event of an alarm. Both softwares run on a PC under MS Windows, are at no charge, and can be downloaded from this website.

Laureate Ethernet & 4-20 mA Output Thermocouple Temperature Transmitter

Operation as a Fast ON/OFF Controller or Supervisory Monitor

With the optional dual solid state relay output option, which has a typical response time of only 17 ms, Laureate temperature meters and transmitters can serve as extremely fast and accurate ON/OFF controllers for closed-loop temperature control. They can also serve as supervisory process monitors and provide alarms or shutoffs when processes exceed normal limits.

Multiple setpoint operating modes are individually selectable for each relay, as explained in the dual-setpoint controller page. Relay duty cycles and chatter can be minimized with programmable hysteresis and time delays. A band deviation operating mode can be selected for each relay, where an alarm is generated whenever the reading is a selected number of counts above or below the setpoint. The relay modes have to be non-latching, since 4-20 mA temperature transmitters do not offer external reset.