Features
Transmitter optimized for weighing applications
Accuracy of 0.01% of reading ± 2 counts
4- or 6-wire hookup to avoid lead resistance effects
10V excitation supply for up to four 350-ohm load cells in parallel
Count by 1, 2, 5, 10, 20, 50 or 100 with rounding
Transmitter toggles between gross or net weight
Auto-tare or manual tare, with tare value stored in non-volatile memory
All input ranges are user selectable and factory calibrated
Up to 60 conversions per second, Ideal for peak or valley capture
Digital span adjust from 0 to ±99,999, zero adjust from -99,999 to +99,999
4-20 mA, 0-20 mA, 0-10V or -10V to +10V transmitter output, (isolated)
Analog output resolution 0.0015% of span, accuracy ±0.02% of span
RS232 or RS485 serial data, Modbus or Laurel ASCII protocol (isolated)
Dual 120 mA solid state relays for alarm or control (isolated)
5V, 10V, 12V, or 24V dc transducer excitation output (isolated)
Power 85-264 Vac / 90-300 Vdc or 10-48 Vdc / 12-32 Vac (isolated)
DIN rail mount housing, 22.5 mm wide, detachable screw-clamp connectors
Operating temperature from -40°C to 70°C (-40°F to 158°F) Optional - Extended allows up to 180 data points for custom curve linearization and a rate derived from consecutive readings.
The Laureate™ LT Series DIN rail analog transmitter with serial data communication and analog outputs for versatile connectivity.
The digitally programmable transmitter features two relays for alarm or control. The series offers exceptional accuracy of 0.01% of reading ± 2 counts, with high read rates at up to 60 or 50 conversions per second. The LT Series transmitters offer the same high performance, signal conditioning, and programmable features as Laureate digital panel meters, counters, and timers.
The Laureate 4-20 mA, 0-20 mA, 0-10V or -10V to +10V and RS232/RS485 output transmitter for scale weighing applications offers the same high performance, signal conditioning, and programmable features as Laureate digital panel meters, counters, and timers. It provides six voltage input ranges and four current input ranges, all factory calibrated and jumper selectable. This compact, inexpensive, and highly accurate transmitter features special firmware for weighing applications. It is available with the Laureate load cell or DC signal conditioner board. If you do not need the special weighing firmware, consider using the Laureate load cell transmitter or Laureate process transmitter.
The DC signal conditioner board can used in lieu of the load cell signal conditioner board, be set to ratiometric operation, and be used with the transmitter's 5 Vdc or 10 Vdc excitation. It's most sensitive full-scale range is ±200 mV with 10 µV resolution, while the load cell signal conditioner board offers most sensitive ranges of ±20 mV and ±50 mV, both with 1 µV resolution. Transmitters with both boards offer an accuracy of 0.01% of full scale ± 2 counts.
Display & Setpoint Functions for Weighing Applications
Relay setpoint offset. The ON/OFF setpoint control action can be programmed to occur with a specified offset. For instance, if bags are to be filled to 100 lbs and the material delivery spout is known to hold and dispense an additional 2.5 lbs following shut-off, an offset of -2.5 lbs can be programmed. The setpoint can then be set to 100 lbs, and the filling valve will be automatically shut off when the measured weight reaches 97.5 lbs.
Count-by function. The weight transmitter can be programmed so that it can be displayed via Laurel's Instrument Setup Software, which runs on a PC under MS Windows, is rounded off to multiples of 1, 2, 5, 10, 20, 50 or 100. For example, if count-by 10 is selected, the transmitter will display 20 for an internal count of 15 to 24.
Fixed right-hand dummy zero. The transmitter can be shifted to the left for a fixed zero to the right, allowing values up to 999,990. The right-hand zero precludes the use of decimal points.
Auto-zero function. An auto-zero limit from 0 to 9 counts can be programmed to compensate for load cell drift. Whenever the transmitter comes to rest within that limit from zero, it will auto-zero. Entering 0 disables auto-zero.
Easy scale calibration is achieved using a simple two-point calibration method. First, the desired LO IN reading is set to 0, and the desired HI IN reading is set to a desired value. With no weight on the scale, a button is pushed for LO IN. With a known weight on the scale, that button is pushed again for HI IN. The transmitter then automatically computes scale and offset for readout up to five digits in weight units.
Scale and offset can be provided by either of two user-selectable methods:
With the coordinate reading method, the transmitter reads the high and low signal values, and the user enters the desired high an low reading values. The transmitter then calculates the span multiplier and offset. This method is ideal if an external calibration reference is available.
With the manual coordinate method, the user enters the high and low input values in Volts plus the desired high and low reading values. This method is suitable if no external calibration reference is available.
A built-in, (isolated), 10V, 120 mA excitation supply can power up to four 350-ohm load cells in parallel. Load cell connection can be via 4 or 6 wires. With 4-wire load connection, the transmitter operates in a ratiometric mode to eliminate errors due to power supply variations. With 6-wire load connection, it also compensates for lead resistance, allowing long cable runs.
All signal conditioner board ranges are factory-calibrated, with calibration factors for each range securely stored in an onboard EEPROM. These factors can be scaled via software to accommodate external shunts, enabling field replacement of signal conditioner boards without necessitating recalibration of the associated transmitter. For optimal accuracy, factory recalibration is recommended annually. All Laurel Electronics instruments undergo factory calibration using the industry-leading Fluke calibrators, which are recalibrated yearly and certified traceable to national standards, ensuring the highest level of precision and reliability.
The optional extended Laureate computer board enhances Laureate transmitter by displaying rates derived from successive readings and enabling highly accurate custom curve linearization. For example, it can calculate liquid volume or flow rate in a horizontal cylindrical tank using levels from a 4-20 mA transmitter. Setup is straightforward: users input up to 180 data points into a spreadsheet or text file, and the computer calculates spline-fit segments, which are then downloaded to the transmitter for precise operation.
Laureate Transmitters are easily programmed with Laurel’s free Instrument Setup Software, downloadable from our website and compatible with Windows PCs, requiring a data interface board for setup.
High read rate of up to 50 or 60 conversions per second, the Laureate™ LT Series transmitter uses Concurrent Slope (US Pat. 5,262,780) analog-to-digital conversion to integrate signals over a full power line cycle (50 Hz or 60 Hz). This read rate enables peak and valley capture, real-time computer interfacing, and control applications. Peak and valley values are automatically captured and can be viewed using Laurel’s free Instrument Setup Software (compatible with Windows PCs) or transmitted as serial data.
Standard Hardware Features of Laureate LT Transmitters Include:
Serial communications output, (isolated), RS232 or RS485 (half or full duplex), jumper selectable. Three protocols are user selectable: Modbus RTU, Modbus ASCII, or Laurel ASCII. Modbus operation is fully compliant with Modbus Over Serial Line Specification V1.0 (2002). The Laurel ASCII protocol is simpler than the Modbus protocol and is recommended when all devices are Laureates.
4-20 mA, 0-10V or -10V to +10V analog transmitter output, (isolated), jumper-selectable and user scalable. All selections provide 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. Note that Ethernet data I/O is provided by Laurel's LTE series transmitters.
Dual solid state relays, (isolated), for alarm or control. Rated 120 mA at 130 Vac or 180 Vdc.
Selectable transducer excitation output, (isolated), user selectable 5V@100 mA, 10V@120 mA, 12V@100mA, or 24V@50 mA.
Power 85-264 Vac, (isolated), low-voltage 10-48 Vdc or 12-32 Vac power is optional.
Digital signal filtering modes can be selected to ensure stable readings in electrically noisy environments.
An unfiltered selection provides true peak and valley readings and aids in control applications.
A batch average filter selection averages each 16 conversions.
An adaptive moving average filter selection provides a choice of 8 time constants from 80 ms to 9.6 seconds. When a significant change in signal level occurs, the filter adapts by briefly switching to the shortest time to follow the change, then reverts back to its selected time constant. An Auto setting selects the time constant selection based on signal noise.
Two tare functions: auto-tare and manual tare. In auto-tare, an input line is grounded by an external pushbutton. This causes the current weight, which is normally the empty weight of the container to be stored in memory as an offset. In manual tare, the tare value can be entered manually via a control input pushbutton or using Laurel's free Instrument Setup Software.
Peak and valley values are automatically captured. These may be displayed via Laurel's free Instrument Setup Software, which runs on a PC under MS Windows or can be transmitted as serial data.
Two control inputs (CMOS/TTL levels, logic 0 = tied to digital ground, logic 1 = open) or dry contacts that can be set to control / activate 14 transmitter commands.
An (isolated) 5, 10, 12, or 24 Vdc excitation output is standard to power transducers or two-wire transmitters. Ratiometric operation, which automatically compensates for changes in the applied excitation, is jumper selectable for applications, such as bridges, where the signal to be measured is proportional to the excitation level.
LT series DIN rail Transmitters & signal conditioners can be interfaced to a wide range of sensors and transducers using one of seven available plug-in signal conditioner boards. The transmitters duplicate the high performance (high accuracy and high read rate) and extensive programmable features of Laureate 1/8 DIN digital panel meters, counters, and timers. They utilize the same signal conditioners boards, much of the same firmware, and Laurel's free Windows-based Instrument Setup Software. They come in a compact DIN rail mount package with detachable screw-clamp connectors for easy wiring.
The LT series Transmitters feature isolated, user-selectable analog outputs (4-20 mA, 0-20 mA, 0-10V, or -10V to +10V), an RS232 or RS485 serial data interface, and dual 120 mA solid state AC/DC relays. Most models, except those with temperature or AC RMS signal conditioners, include an isolated 5, 10, 12, or 24 Vdc transducer excitation output.
Connecting Laureate LT Transmitters to a Local Area Network (LAN)
Up to 30 Laureate LT Transmitters and/or Digital Panel Meters can be configured for RS485 and daisy-chained to an LT Transmitter for seamless LAN integration. Alternatively, Laurel LTE series Ethernet transmitters can connect directly to a LAN via an Ethernet cable. Setup for both configurations is streamlined using Laurel’s free Instrument Setup Software, which simplifies node discovery and transmitter configuration.
Flexible Communication Options for LT Transmitters
Laureate Transmitters can be equipped with Laurel communication boards to support various interfaces and protocols. These include serial interfaces with ASCII or Modbus RTU protocols, and Ethernet interfaces with web access, ASCII, or Modbus TCP/IP protocols, ensuring versatile connectivity for your commercial applications.
Features
- Transmitter optimized for weighing applications
- Accuracy of 0.01% of reading ± 2 counts
- 4- or 6-wire hookup to avoid lead resistance effects
- 10V excitation supply for up to four 350-ohm load cells in parallel
- Count by 1, 2, 5, 10, 20, 50 or 100 with rounding
- Transmitter toggles between gross or net weight
- Auto-tare or manual tare, with tare value stored in non-volatile memory
- All input ranges are user selectable and factory calibrated
- Up to 60 conversions per second, Ideal for peak or valley capture
- Digital span adjust from 0 to ±99,999, zero adjust from -99,999 to +99,999
- 4-20 mA, 0-20 mA, 0-10V or -10V to +10V transmitter output, (isolated)
- Analog output resolution 0.0015% of span, accuracy ±0.02% of span
- RS232 or RS485 serial data, Modbus or Laurel ASCII protocol (isolated)
- Dual 120 mA solid state relays for alarm or control (isolated)
- 5V, 10V, 12V, or 24V dc transducer excitation output (isolated)
- Power 85-264 Vac / 90-300 Vdc or 10-48 Vdc / 12-32 Vac (isolated)
- DIN rail mount housing, 22.5 mm wide, detachable screw-clamp connectors
- Operating temperature from -40°C to 70°C (-40°F to 158°F)
Optional - Extended allows up to 180 data points for custom curve linearization and a rate derived from consecutive readings.
The Laureate™ LT Series DIN rail analog transmitter with serial data communication and analog outputs for versatile connectivity.
The digitally programmable transmitter features two relays for alarm or control. The series offers exceptional accuracy of 0.01% of reading ± 2 counts, with high read rates at up to 60 or 50 conversions per second. The LT Series transmitters offer the same high performance, signal conditioning, and programmable features as Laureate digital panel meters, counters, and timers.
The Laureate 4-20 mA, 0-20 mA, 0-10V or -10V to +10V and RS232/RS485 output transmitter for scale weighing applications offers the same high performance, signal conditioning, and programmable features as Laureate digital panel meters, counters, and timers. It provides six voltage input ranges and four current input ranges, all factory calibrated and jumper selectable. This compact, inexpensive, and highly accurate transmitter features special firmware for weighing applications. It is available with the Laureate load cell or DC signal conditioner board. If you do not need the special weighing firmware, consider using the Laureate load cell transmitter or Laureate process transmitter.
The DC signal conditioner board can used in lieu of the load cell signal conditioner board, be set to ratiometric operation, and be used with the transmitter's 5 Vdc or 10 Vdc excitation. It's most sensitive full-scale range is ±200 mV with 10 µV resolution, while the load cell signal conditioner board offers most sensitive ranges of ±20 mV and ±50 mV, both with 1 µV resolution. Transmitters with both boards offer an accuracy of 0.01% of full scale ± 2 counts.
Display & Setpoint Functions for Weighing Applications
- Relay setpoint offset. The ON/OFF setpoint control action can be programmed to occur with a specified offset. For instance, if bags are to be filled to 100 lbs and the material delivery spout is known to hold and dispense an additional 2.5 lbs following shut-off, an offset of -2.5 lbs can be programmed. The setpoint can then be set to 100 lbs, and the filling valve will be automatically shut off when the measured weight reaches 97.5 lbs.
- Count-by function. The weight transmitter can be programmed so that it can be displayed via Laurel's Instrument Setup Software, which runs on a PC under MS Windows, is rounded off to multiples of 1, 2, 5, 10, 20, 50 or 100. For example, if count-by 10 is selected, the transmitter will display 20 for an internal count of 15 to 24.
- Fixed right-hand dummy zero. The transmitter can be shifted to the left for a fixed zero to the right, allowing values up to 999,990. The right-hand zero precludes the use of decimal points.
- Auto-zero function. An auto-zero limit from 0 to 9 counts can be programmed to compensate for load cell drift. Whenever the transmitter comes to rest within that limit from zero, it will auto-zero. Entering 0 disables auto-zero.
Easy scale calibration is achieved using a simple two-point calibration method. First, the desired LO IN reading is set to 0, and the desired HI IN reading is set to a desired value. With no weight on the scale, a button is pushed for LO IN. With a known weight on the scale, that button is pushed again for HI IN. The transmitter then automatically computes scale and offset for readout up to five digits in weight units.
Scale and offset can be provided by either of two user-selectable methods:
- With the coordinate reading method, the transmitter reads the high and low signal values, and the user enters the desired high an low reading values. The transmitter then calculates the span multiplier and offset. This method is ideal if an external calibration reference is available.
- With the manual coordinate method, the user enters the high and low input values in Volts plus the desired high and low reading values. This method is suitable if no external calibration reference is available.
A built-in, (isolated), 10V, 120 mA excitation supply can power up to four 350-ohm load cells in parallel. Load cell connection can be via 4 or 6 wires. With 4-wire load connection, the transmitter operates in a ratiometric mode to eliminate errors due to power supply variations. With 6-wire load connection, it also compensates for lead resistance, allowing long cable runs.
All signal conditioner board ranges are factory-calibrated, with calibration factors for each range securely stored in an onboard EEPROM. These factors can be scaled via software to accommodate external shunts, enabling field replacement of signal conditioner boards without necessitating recalibration of the associated transmitter. For optimal accuracy, factory recalibration is recommended annually. All Laurel Electronics instruments undergo factory calibration using the industry-leading Fluke calibrators, which are recalibrated yearly and certified traceable to national standards, ensuring the highest level of precision and reliability.
The optional extended Laureate computer board enhances Laureate transmitter by displaying rates derived from successive readings and enabling highly accurate custom curve linearization. For example, it can calculate liquid volume or flow rate in a horizontal cylindrical tank using levels from a 4-20 mA transmitter. Setup is straightforward: users input up to 180 data points into a spreadsheet or text file, and the computer calculates spline-fit segments, which are then downloaded to the transmitter for precise operation.
Laureate Transmitters are easily programmed with Laurel’s free Instrument Setup Software, downloadable from our website and compatible with Windows PCs, requiring a data interface board for setup.
High read rate of up to 50 or 60 conversions per second, the Laureate™ LT Series transmitter uses Concurrent Slope (US Pat. 5,262,780) analog-to-digital conversion to integrate signals over a full power line cycle (50 Hz or 60 Hz). This read rate enables peak and valley capture, real-time computer interfacing, and control applications. Peak and valley values are automatically captured and can be viewed using Laurel’s free Instrument Setup Software (compatible with Windows PCs) or transmitted as serial data.
Standard Hardware Features of Laureate LT Transmitters Include:
- Serial communications output, (isolated), RS232 or RS485 (half or full duplex), jumper selectable. Three protocols are user selectable: Modbus RTU, Modbus ASCII, or Laurel ASCII. Modbus operation is fully compliant with Modbus Over Serial Line Specification V1.0 (2002). The Laurel ASCII protocol is simpler than the Modbus protocol and is recommended when all devices are Laureates.
- 4-20 mA, 0-10V or -10V to +10V analog transmitter output, (isolated), jumper-selectable and user scalable. All selections provide 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. Note that Ethernet data I/O is provided by Laurel's LTE series transmitters.
- Dual solid state relays, (isolated), for alarm or control. Rated 120 mA at 130 Vac or 180 Vdc.
- Selectable transducer excitation output, (isolated), user selectable 5V@100 mA, 10V@120 mA, 12V@100mA, or 24V@50 mA.
- Power 85-264 Vac, (isolated), low-voltage 10-48 Vdc or 12-32 Vac power is optional.
Digital signal filtering modes can be selected to ensure stable readings in electrically noisy environments.
- An unfiltered selection provides true peak and valley readings and aids in control applications.
- A batch average filter selection averages each 16 conversions.
- An adaptive moving average filter selection provides a choice of 8 time constants from 80 ms to 9.6 seconds. When a significant change in signal level occurs, the filter adapts by briefly switching to the shortest time to follow the change, then reverts back to its selected time constant. An Auto setting selects the time constant selection based on signal noise.
Two tare functions: auto-tare and manual tare. In auto-tare, an input line is grounded by an external pushbutton. This causes the current weight, which is normally the empty weight of the container to be stored in memory as an offset. In manual tare, the tare value can be entered manually via a control input pushbutton or using Laurel's free Instrument Setup Software.
Peak and valley values are automatically captured. These may be displayed via Laurel's free Instrument Setup Software, which runs on a PC under MS Windows or can be transmitted as serial data.
Two control inputs (CMOS/TTL levels, logic 0 = tied to digital ground, logic 1 = open) or dry contacts that can be set to control / activate 14 transmitter commands.
An (isolated) 5, 10, 12, or 24 Vdc excitation output is standard to power transducers or two-wire transmitters. Ratiometric operation, which automatically compensates for changes in the applied excitation, is jumper selectable for applications, such as bridges, where the signal to be measured is proportional to the excitation level.
LT series DIN rail Transmitters & signal conditioners can be interfaced to a wide range of sensors and transducers using one of seven available plug-in signal conditioner boards. The transmitters duplicate the high performance (high accuracy and high read rate) and extensive programmable features of Laureate 1/8 DIN digital panel meters, counters, and timers. They utilize the same signal conditioners boards, much of the same firmware, and Laurel's free Windows-based Instrument Setup Software. They come in a compact DIN rail mount package with detachable screw-clamp connectors for easy wiring.
The LT series Transmitters feature isolated, user-selectable analog outputs (4-20 mA, 0-20 mA, 0-10V, or -10V to +10V), an RS232 or RS485 serial data interface, and dual 120 mA solid state AC/DC relays. Most models, except those with temperature or AC RMS signal conditioners, include an isolated 5, 10, 12, or 24 Vdc transducer excitation output.
Connecting Laureate LT Transmitters to a Local Area Network (LAN)
Up to 30 Laureate LT Transmitters and/or Digital Panel Meters can be configured for RS485 and daisy-chained to an LT Transmitter for seamless LAN integration. Alternatively, Laurel LTE series Ethernet transmitters can connect directly to a LAN via an Ethernet cable. Setup for both configurations is streamlined using Laurel’s free Instrument Setup Software, which simplifies node discovery and transmitter configuration.
Flexible Communication Options for LT Transmitters
Laureate Transmitters can be equipped with Laurel communication boards to support various interfaces and protocols. These include serial interfaces with ASCII or Modbus RTU protocols, and Ethernet interfaces with web access, ASCII, or Modbus TCP/IP protocols, ensuring versatile connectivity for your commercial applications.
