Features
- Two independently scalable totals for Channels A & B
- Inputs from NPN or PNP proximity switches, contact closures, digital logic, or magnetic pickups down to 12 mV, pulse rates to 1 MHz
- Two independently field-scalable pulse input channels
- Up counting from zero to preset value using positive scale factor
- Down counting from preset to zero using negative scale factor
- Totals stored in non-volatile memory
- 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 plus rate and total simultaneously, ratio (A/B), draw (A/B-1), other arithmetic functions (AxB, A+B, A-B), phase angle, stopwatch, up/down counting, batching operation, linearization of nonlinear inputs.
Certificates of Compliance
The Laureate 4-20 mA, 0-20 mA, 0-10V or -10V to +10V and RS232/RS485 output transmitter for pulse input to 4-20 mA converter and serial data output accepts totals from two independently scalable input channels from a wide range of pulse sources, such as NPN or PNP proximity switches, contact closures, digital logic, magnetic pickups down to 12 mV, or AC voltages to 250 Vac. Input pulse rates can be as high as 1 MHz.
With a Standard main board, the transmitter output can be scaled to track total (such as gallons) or rate (such as gallons per minute). Square root extraction is standard.
With an Extended main board, the transmitter can also:
- Count up to a preset or down from a preset to zero. Such applications typically utilize the transmitter's two solid state relays, which are standard. External reset of totals is via a special three-position screw terminal connector.
- Perform custom-curve linearization on rate or total, for example to extend the range of transducers. Exceptionally accurate custom-curve linearization is provided by a curvilinear spline fit with up to 180 data points.
- Combine channels A and B arithmetically so that the transmitter output tracks A+B (e.g., sum of two flows or totals), A-B (e.g., difference of two flows or totals), AxB (e.g., horsepower as product of force and RPM), A/B (ratio of two flow or totals), and A/B-1 (draw or relative elongation of material between rollers).
The dual-channel signal conditioner used for pulse detection accepts inputs from proximity switches with PNP or NPN output, TTL or CMOS logic, magnetic pickups, contact closures, and voltage signals from 12 mV to 250 Vac. Jumper selections provide optimum operation for different sensor types and noise conditions. A built-in 5V, 10V, 12V, or 24V dc excitation supply can power proximity switches and other sensors, and eliminate the need for an external power supply.
Exceptional Accuracy and Stability. Laureate transmitters determine frequency by taking the inverse of period as measured with a calibrated quartz crystal time base. This results in extremely accurate and stable 6-digit internal readings (±999,999 counts), which are then processed in software. The analog output is generated by an ultra-linear 16-bit (65,536 step) digital-to-analog converter (DAC) for 0.02% output accuracy. The update rate of the transmitter output is a programmed gate time + 30 ms + 0-2 signal periods. For a 60 Hz signal, the update rate would be 20 per second. Such fast update rates are ideal for alarm and control.
The update rate of the transmitter output is a programmed gate time + 30 ms + 0-2 signal periods. For a 60 Hz signal, the update rate would be 20 per second. Such fast update rates are ideal for alarm and control.
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.
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.
Standard 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-channel pulse inputs for voltage signals, NPN or PNP proximity switches, contact closures, magnetic pickups or flow meters.
- Dual solid state relays, (isolated), for alarm or control. Rated 120 mA at 130 Vac or 170 Vdc.
- Selectable transducer excitation output, (isolated), user selectable 5V@100 mA, 10V@120 mA, 12V@100 mA, 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.
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, 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 accessible from this page include a 4-20 mA, 0-20 mA, 0-10V, or -10V to +10V analog output (isolated, user selectable), an RS232 or RS485 serial data interface (isolated, user selectable), and dual 120 mA solid state AC/DC relays (isolated). An (isolated) 5, 10, 12, or 24 Vdc transducer excitation output is included with all models other than those with a temperature or AC RMS signal conditioner.
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.
| LT Transmitter Signal Input & Function | Model Series | Analog Output | RS232 & RS485 | Dual Relays | |
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| 1 | DC Input Voltage and Current | LT-DC |  |
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| 2 | AC RMS Voltage or Current | LT-RMS | |
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| 3 | Process Voltage or Current | LT-P | |
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| 4 | Weighing Applications | LT-WA | |
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| 5 | Load Cell & Microvolt Signals | LT-WM | |
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| 6 | Thermocouple (Types J, K, T, E, N, R, S) | LT-TC | |
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| 7 | RTD Temperature | LT-RTD | |
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| 8 | Resistance in Ohms | LT-R | |
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| 9 | Frequency, Rate, Speed | LT-FR | |
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| 10 | Pulse Input Totalizer | LT-FR | |
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| 11 | Process Signal Totalizer | LT-VF | |
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| 12 | Sum, Difference, Ratio, Product of 2 Inputs | LT-FR | |
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| 13 | Batch Controller Pulse Input | LT-FR | |
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| 14 | Batch Controller Analog Input | LT-FR | |
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| 15 | On/Off Duty Cycle | LT-FR | |
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| 16 | Stopwatch Timing for Single Events | LT-FR | |
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| 17 | Average Time of Periodic Events | LT-FR | |
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| 18 | AC Phase Angle and Power Factor | LT-FR | |
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| 19 | Quadrature Position or Rate | LT-QD | |
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Laureate Transmitter with Dual Pulse Totalizing Inputs
| Pulse Input | ||||
|---|---|---|---|---|
| Types | AC, pulses from NPN, PNP transistors, contact closures, magnetic pickups | |||
| Signal Ground | Common ground for channels A & B. | |||
| Minimum Signal | Nine ranges from (-12 to +12 mV) to (+1.25 to +2.1V). | |||
| Maximum Signal | 250 Vac | |||
| Maximum Frequency | 1 MHz, 30 kHz, 250 Hz (selectable). | |||
| Contact Debounce | 0, 3, 50 ms (selectable). | |||
| Recalibration: All ranges are calibrated at the factory. Recalibration is recommended every 12 months. | ||||
| Analog Output (standard) | ||||
| Output Levels | 4-20 mA, 0-20 mA, 0-10 Vdc, -10 to +10Vdc (user selectable) | |||
| Compliance, 4-20 mA | 10V (0-500Ω load) | |||
| Compliance, 0-10V | 2 mA (5 kΩ or higher load) | |||
| Output Resolution | 16 bits (65,536 steps) | |||
| Output Accuracy | 0.02% of output span | |||
| Output Update Rate | Programmed gate time + 30 ms + 0-2 signal periods | |||
| Output Isolation | 250V rms working, 2.3 kV rms per 1 minute test | |||
| Serial Data Output (standard) | ||||
| Signal Types | RS232 or RS485 (half or full duplex), jumper selectable | |||
| Data Rates | 300, 600, 1200, 2400, 4800, 9600, 19200 baud | |||
| Output Isolation | 250V rms working, 2.3 kV rms per 1 min test | |||
| Serial Protocols | Modbus RTU, Modbus ASCII, Laurel ASCII | |||
| Modbus Compliance | Modbus over Serial Line Specification V1.0 (2002) | |||
| RS232/485 Connector | Screw terminals for easy daisy chaining | |||
| Digital Addresses | 247 for Modbus, 31 for Laurel ASCII | |||
| Dual Relay Output (standard) | ||||
| Relay Type | Two solid state relays, SPST, normally open, Form A | |||
| Load Rating | 120 mA at 140 Vac or 180 Vdc | |||
| Excitation Output (standard) | ||||
| 5 Vdc | 5 Vdc ± 5%, 100 mA (jumper selectable) | |||
| 10 Vdc | 10 Vdc ± 5%, 120 mA (jumper selectable) | |||
| 12 Vdc | 12 Vdc ± 5%, 100 mA (jumper selectable) | |||
| 24 Vdc | 24 Vdc ± 5%, 50 mA (jumper selectable) | |||
| Output Isolation | 50 Vdc from signal ground | |||
| Power Input | ||||
| Standard Power | 85-264 Vac or 90-300 Vdc | |||
| Low Power Option | 10-48 Vdc or 12-32 Vac | |||
| Power Frequency | DC or 47-63 Hz | |||
| Power Isolation | 250V rms working, 2.3 kV rms per 1 min test | |||
| Power Consumption at 24V | 1.5W typical, 3W with max excitation output | |||
| Environmental | ||||
| Operating Temperature | -40°C to 70°C (-40°F to 158°F) | |||
| Storage Temperature | -40°C to 85°C (-40°F to 185°F) | |||
| Relative Humidity | 95% at 40°C, non-condensing | |||
| Cooling Required | Mount transmitters with ventilation holes at top and bottom. Leave 6 mm (1/4") between transmitters, or force air with a fan. | |||
| Mechanical | ||||
| Enclosure | Rugged black polycarbonate housing material | |||
| Mounting | 35 mm rail per DIN EN 50022 | |||
| Dimensions | 129 x 104 x 22.5 mm case | |||
| Connectors | Detachable screw clamp connectors meet VDE / IEC / UL / CSA standards. RJ45 jack for Ethernet | |||
| Tightening Torque | Screw terminal connectors: 5 lb-in (0.56 Nm) | |||
| Weight | Complete transmitter: 183 g (6.5 oz) | |||
| Replacement Case Screws | ||||
| Size | 6 | |||
| Thread Pitch | 6-19 | |||
| Length | 1/2" | |||
| Head Style | Pan Head | |||
| Drive Style | Phillips | |||
| Head Diameter | 0.256-0.270 | |||
| Head Height | 0.087-0.097 | |||
| Full/Partial Thread | Full | |||
| Drive Size | 2 | |||
| Material | Steel | |||
| Finished | Black Oxide | |||
| General | ||||
| Programming | Utilize Laurel's free Instrument Setup Software, which runs on a PC under MS Windows. | |||
| Security | Lockout options available using Laurel's free Instrument Setup Software. | |||
| Warranty | 3 years parts & labor | Recalibration: All ranges are calibrated at the factory. Recalibration is recommended every 12 months. | ||
Transmitter Pinout
Free Instrument Setup Software for Series 2 Laureates
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| 1/8 DIN Digital Panel Meters | DIN Rail Transmitters |
Free Downloadable Windows-based Instrument Setup (IS) software (Data Interface Board Required) for use with our programmable Digital Panel Meters, Scale Meters, Counters, Timers, Remote Displays, and Transmitters, are an easy method to set up Laureate 1/8 DIN digital panel meters, counters, timers, remote displays, and DIN-rail transmitters, as explained in the Instrument Setup Software Manual. Laureate 1/8 DIN instruments can also be set up from the front panel, as explained in their respective Owners Manuals. Instrument Setup software is of benefit whether or not the PC is connected to the instrument.
- When the PC is connected to the instrument, Instrument Setup software can retrieve the setup file from the instrument or open a default setup file or previously saved setup file from disk View Setup, then provides graphical user interface (GUI) screens with pull-down menus applicable to input, display, scaling, filtering, alarms, communications, analog output, and front panel lockouts. Fields that are not applicable to the instrument as configured are either left out or grayed out. Clicking on any item will bring up a detailed Help screen for that item. After editing, the setup file can be downloaded, uploaded to the instrument, or saved to a disk. The same setup file can then be downloaded into multiple instruments.
- When the PC is not connected to the instrument, the above GUI screens can be used to set up a virtual instrument. The setup file can then be saved to disk. Switching toView Menu then brings up a screen with the required front panel programming steps. This view can be printed out for use at the instrument site and to serve as a hard copy record.
Download Free Instrument Setup Software
Installation
Set User Account Control (UAC) of MS Windows to "Never notifiy me" so that Instrument Setup Software can create directories. The UAC change screen can be reached as follows:
- Under Windows 7, click on the Windows Start button in the lower left of the desktop and enter "UAC" in the search field.
- Under Windows 8, navigate to Control Panel, then to the "User Accounts and Family Safety" section, and click on "Change User Account Control Settings."
- Under Windows 10, click on the Windows Start button in the lower left of the desktop, then on "Settings", and enter "UAC" in the search field.
- Reboot your computer for the changed UAC setting to take effect.
RJ11-to-DB9 cable with rear view of DB9 connector to PC
RS232 cable, meter to PC, P/N CBL01
Laureate 1/8 DIN Laureate instruments must be equipped with a serial communications board and be connected to the computer via a serial communications cable. The connection can be via RS232, RS485, USB or Ethernet. Following setup, the serial communications board may be removed from the instrument if desired. The wiring of the RS232 cable is illustrated above with end views of the two connectors.
Laureate LT Series transmitters come standard with a 3-wire serial interface, which can be jumpered for RS232 or RS485.
Laureate LTE Series transmitters come standard with an Ethernet interface.
Meter Setup Screens
Click on any of the reduced screens below for a full-size screen view, then click on the Back button of your browser to return to this page. The screens examples below are for a fully-loaded Series 2 Digital Panel Meter (DPM), which is connected to the PC via RS232. If the meter is a Series 1 meter (pre-2007), this is sensed by the software, and somewhat different screens are brought up. Please see Series 1 setup screens.
Welcome Screen
From the computer desktop, click on Start > Programs > IS2 > IS2. Or click on the IS icon on your desktop. This splash screen will be displayed for three seconds. The software revision number is in the lower right.
Communications Selection Screen
Specify your desired communication protocol and the serial communications bus type, which should match the jumper setup of the instrument. Select None if the PC is not connected to the instrument.
Establish Communications Screen
If you selected RS-232, you will be asked to specify the PC Com Port and Baud Rate, which should match the jumper setup of the instrument. Click on Establish. With the right settings, the Communications Established field will light up in green, and the Meter Type will be recognized. If so, click onMain Menu.
Main Menu Screen
Click on File > Default Setup to retrieve the default setup file from disk for your type of meter. Click on File > Open Setupto retrieve a previously saved setup file from disk or on File > Save Setup to save your edited setup file to disk. Click onDPM > Get Setup to retrieve the setup file from your meter or on DPM > Put Setup to download your edited setup file into the meter.
DPM Input + Display Setup Screen
From the Main Menu, click on View > Setup, then on theInput+Display tab. You can now specify the meter hardware, signal type, display mode, and functions of control inputs A and B. Clicking on any item brings up a pull-down menu with the available choices.
DPM Scaling Setup Screen
Click on the Scaling tab, which provides three scaling methods to relate the signal to the displayed reading: 1) Scale and Offset method, 2) Coordinates of two points method, and 3) Reading Coordinates of Two Points method. The last method uses actual high and low signals, and the computer will prompt you.
DPM Filter Setup Screen
Click on the Filter tab, which allows you to specify the digital filter time constant (if any), the adaptive filter threshold, and whether Peak / Valley values are filtered or unfiltered. As for all setup screens, clicking on the F1 key while an item is highlighted brings up a Help screen for that item, as illustrated.
DPM Relay Alarms Setup Screen
Click on the Relay Alarms tab, which allows you to set up Alarms 1 and 2 for the optional dual relay output board. Clicking on any of the four numeric fields changes these to green and brings up a special field to enter the desired numeric value, which is tied to the displayed reading.
DPM Communications Setup Screen
Click on the Communications tab so set up serial communications. In particular, you can special the Serial Protocol and the meter address if multiple meters are to be addressed on the same serial data line.
DPM Analog Output Setup Screen
Click on the Analog Out tab so set up the optional analog output board. Three output ranges are selectable, the endpoints of which can be tied to user-specified High and Low readings.
DPM Lockouts Setup Screen
Click on the Lockouts tab to check off menu items which will no longer be accessible from the front panel of the meter. This will simplify meter operation and prevent unintended setup changes.
Meter Setup Utilities
DPM Front Panel Setup Screen
As an aid to programming the meter from the front panel when a serial connection is not available, you can return to the Main Menu and click on View > Menu. The required sequence of front panel screens will then be displayed. Click on any step in the sequence for the meaning of each digit, as illustrated for the FILtEr step. For a hardcopy, simply press on Print.
DPM Jumper Setup Screen
Specify your desired communication protocol and the serial communications bus type, which should match the jumper setup of the instrument. Select None if the PC is not connected to the instrument.
DPM Jumper Setup Screens
Click on any of the displayed plug-in boards, and you will be presented with the jumper positions and electrical connections for your selected board. This minimizes the need to refer to the printed manual.
DPM Commands Screen
This page allows you set up external input, serial communications, an analog output proportional to the display (optional), and lockouts for Laureate digital counters. The grayed out area at the top right of the screen applies to Laureate remote displays.
Graphical Output Screens (not available with Ethernet)
From the Main Menu, click on Readings if your PC is connected to the meter. A pull-down menu then offers three choices: List, Plot and Graph.
- List presents the latest readings in a 20-row by 10-column table. Press Pause at any time to freeze the display. This is one method to capture peak readings.
- Plot generates a plot of readings vs. time in seconds. It effectively turns the DPM-PC combination into a printing digital oscilloscope.
- Graph generates a histogram where the horizontal axis is the reading and the vertical axis is the number of occurrences of readings. The display continually resizes itself as the number of readings increases.
DPM Calibration Screens
Click on the Scaling tab, which provides three scalClick on the Scaling tab, which provides three scaling methods to relate the signal to the displayed reading: 1) Scale and Offset method, 2) Coordinates of two points method, and 3) Reading Coordinates of Two Points method. The last method uses actual high and low signals, and the computer will prompt you.
Frequency Meter Calibration Screen
Calibration of the quartz crystal of the Laureate frequency meter requires the input of a known frequency from a calibrator. Apply the frequency, then enter the frequency in Hertz. Calibration will be automatic, with storage of the calibration factor stored in non-volatile memory.
Dimensions
Dimensioned CAD assembly drawings in EPRT, STEP, x_t, .dwg, pdf file formats: Laureate-transmitter-case.zip (zipping prevents browser from opening CAD files as text files).
| Up/Down Totalizing | |
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Up/down totalizing is provided by a mode of the Extended totalizing transmitter where pulses are either added or subtracted on Channel A based on a direction input on Channel B. The unit can also be programmed so that counting by Channel A is inhibited by an input on Channel B. |
| Combining Two Totals | |
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A+B, A-B, A/B and AxB arithmetic functions are available with the Extended totalizing transmitter. A+B can sum two totals, while A-B subtracts the outflow total from inflow total. A/B ratio applied to two totals helps assure the proper mixing of components. |
| Up or Down Counting with Preset | |
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A single Laureate dual-channel totalizing transmitter will handle two repetitive fill operations by counting from zero up to a preset, or down from a preset to zero. The dual relay option is required. |
| Machine ON Time and Utilization | |
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An easy way to measure the ON time of machines is to count AC line cycles and scale the total to hours. To display machine utilization or duty cycle in percent, use the Extended totalizing transmitter. Connect Channel A to switched AC and Channel B to the AC line, and apply a 100 multiplier to the A/B ratio. |
| Custom Curve Linearization | |
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The Extended version of the Laureate dual channel totalizing transmitter can transmit scaled rate or total for the same channel at the push of a button, and alarm both the rate and total. The Extended version can also do curve linearization, thereby extending the working range and accuracy of flow transducers. |
CAL-Digital
Certificate of Calibration
$65.00
CBL02
USB-to-RS232 Adapter Cable
$47.00
CBL04
RS232 Cable for LT Transmitters
$47.00CBL12
12-foot Power Cable
$47.00CBL6
6-foot Power Cable
$41.00What Is the LT DIN Rail Digital Transmitter for Pulse Input Totalizer Applications?
Where a rate meter tracks how fast something is happening, a totalizer tracks how much has happened overall — total gallons pumped, total parts produced, total machine run time. This LT DIN Rail Transmitter accepts pulse inputs on two independently scalable channels and accumulates them into a running total, storing that total in non-volatile memory so it survives a power cycle, while also outputting the value as an isolated 4-20 mA analog signal and digital serial data.
Up/Down Totalizing
With the Extended board, pulses on Channel A are either added to or subtracted from the running total based on a direction signal on Channel B — so a single transmitter can track net accumulation in either direction rather than only counting up. Counting on Channel A can also be inhibited entirely by a signal on Channel B, useful for pausing accumulation during a non-counted phase of a process.
Combining Two Totals
The same A+B, A-B, A/B, and AxB arithmetic functions available for rates can be applied to totals instead: A+B sums two accumulated totals, A-B nets an outflow total against an inflow total, and A/B applied to two totals helps confirm the proper mixing ratio of two components has been maintained across an entire batch rather than just checking the instantaneous rate.
Up or Down Counting with a Preset
A single dual-channel transmitter can independently handle two repetitive fill or count operations, counting up from zero to a preset value or down from a preset value to zero on each channel, with the dual relay option used to trigger an action at completion. External reset of totals is provided via a dedicated three-position screw terminal connector.
Machine ON Time and Utilization
Counting AC line cycles and scaling the total to hours gives a simple way to measure how long a machine has actually been running. To go further and calculate machine utilization or duty cycle as a percentage, Channel A connects to switched AC (power only when the machine is actually running) and Channel B connects to the continuous AC line reference, with a 100x multiplier applied to the A/B ratio to yield a direct percentage.
Simultaneous Rate and Total Display
The Extended version can display and transmit scaled rate and scaled total for the same input channel, switchable at the push of a button, and can alarm from either the rate or the total independently. Custom curve linearization is also available on either rate or total, extending the working range and accuracy of nonlinear flow transducers.
Conclusion
The LT DIN Rail Digital Transmitter for pulse input totalizer applications gives a panel builder a way to accumulate, combine, and act on pulse counts over time, not just measure their instantaneous rate. Whether the need is tracking net up/down totals, combining two totals arithmetically, running independent count-up or count-down operations with a preset, measuring machine utilization, or simply displaying rate and total from the same signal, its dual-channel architecture and non-volatile total storage make it a purpose-built fit for accumulation-based process tracking.
Pulse Input Totalizer Transmitter Frequently Asked Questions
What happens to the total if the transmitter loses power?
Totals are stored in non-volatile memory, so a running total is preserved through a power interruption rather than resetting to zero — the count resumes from where it left off once power is restored.
How does up/down totalizing decide whether to add or subtract a pulse?
A direction signal on Channel B determines whether pulses arriving on Channel A are added to or subtracted from the running total, so the same physical pulse count can represent either accumulation or depletion depending on the state of that direction input.
Can counting be temporarily paused without losing the accumulated total?
Yes — a signal on Channel B can be configured to inhibit counting on Channel A entirely while that signal is present, pausing accumulation without resetting or losing the total that's already been counted.
How is machine utilization actually calculated from two AC inputs?
Channel A is wired to switched AC power that's only present while the machine runs, and Channel B is wired to the continuous AC line as a constant reference; the A/B ratio, multiplied by 100, yields the percentage of total time the machine was actually running.
What's the difference between using this transmitter's external reset versus letting the total run indefinitely?
External reset via the dedicated three-position screw terminal connector lets an operator or automated signal zero the total on demand — useful for batch-based counting where each batch needs its own total — while an indefinite total is more appropriate for cumulative tracking like total machine hours or lifetime production count.
Can this transmitter alarm when a preset count is reached, not just display it?
Yes — the dual solid state relay option is specifically used in up/down counting with preset applications to trigger an action (such as stopping a fill operation) once the count reaches its target, in addition to the total simply being displayed and transmitted.
Does displaying rate and total simultaneously require two separate input channels?
No — the Extended version can derive and display both a scaled rate and a scaled total from the same single input channel, switchable at the push of a button, without needing a second physical input for the total.
Can custom curve linearization be applied to a total, or only to a rate?
It can be applied to either — custom curve linearization corrects for a transducer's nonlinearity regardless of whether the resulting value is displayed as an instantaneous rate or an accumulated total, extending accuracy across the transducer's working range either way.
Can this transmitter combine a total from one channel with a rate from the other?
The arithmetic functions are designed to combine two values of the same type — two rates or two totals — so combining a rate and a total directly in the same arithmetic operation isn't a standard configuration, since the resulting units wouldn't be directly comparable.
Can multiple totalizing transmitters be networked together?
Yes — up to 30 LT Transmitters and/or Digital Panel Meters can be daisy-chained on RS485 for LAN integration, or an LTE series Ethernet transmitter can be used instead for a direct Ethernet connection.
Pulse Input Totalizer Transmitter Questions From the Field
My up/down total doesn't seem to be subtracting correctly even though the direction signal looks right — what should I check?
Confirming the direction input on Channel B is wired to the correct polarity and threshold expected by the transmitter's configuration is the first step, since a direction signal that's technically present but doesn't cross the expected logic threshold can cause the transmitter to treat all pulses as additions regardless of intended direction.
My machine utilization percentage reads higher than I expect given known downtime — what's the likely cause?
This often traces to Channel A (switched AC) picking up power that's present even when the machine isn't actually doing productive work, such as control circuit power staying live during idle periods; confirming Channel A is wired specifically to power that's only active during genuine run time is the standard check.
My preset count-up operation doesn't trigger the relay at the expected count — what should I check?
Verifying the preset value configured in setup software actually matches the intended target, and that the relay is configured to activate at that specific count rather than a different setpoint mode, is the standard first step before suspecting a wiring or hardware fault.
My total reset via the external reset terminal doesn't seem to zero the count reliably — why?
Intermittent reset behavior often points to a marginal connection or signal duration issue at the three-position reset terminal; confirming the reset signal meets the required voltage level and duration, and checking the physical connection at the terminal block, are the standard troubleshooting steps.
My combined A+B total doesn't match manually adding the two individual channel totals — what should I check?
This usually points to a scaling mismatch between the two channels rather than an arithmetic fault, since A+B sums the two channels' already-scaled values; confirming both channels are scaled to the same engineering units before the sum is calculated typically resolves the discrepancy.
Can electrical noise cause my totalizer to count pulses that didn't actually happen?
Yes — electrical noise on the pulse input line can be misinterpreted as legitimate pulses, particularly on long cable runs or in electrically noisy environments; checking cable shielding, grounding, and the selected noise filter setting is the standard remedy for suspected false counting.
My rate and total display (same channel) seem inconsistent with each other — what does that suggest?
Since rate and total are both derived mathematically from the same underlying pulse stream, an apparent inconsistency more often reflects a scaling factor difference between how rate and total were each configured rather than a measurement conflict; verifying both scaling factors are set consistently for the same physical signal is the standard check.
