4-20 mA & Serial Data Output Transmitter and Totalizer

for 0-1 mA, 4-20 mA or 0-10V Analog Proces Signals

Scalable to flow rate or total flow from process signals. DIN Rail mounted, digitally programmable.
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4-20 mA & Serial Data Output Transmitter and Totalizer for 0-1 mA, 4-20 mA or 0-10V Analog Inputs
Standard Features
  • 4-20 mA, 0-20 mA, 0-10V or -10V to +10V transmitter output, 16 bits, isolated
  • RS232 or RS485 serial data output, Modbus or Laurel ASCII protocol, isolated
  • Dual 120 mA solid state relays for alarm or control, isolated
  • 0-1 mA, 4-20 mA or 0-10V process signal input, isolated
  • Converts signal input to a scaled rate or totalized rate
  • Selectable square root for differential flow
  • Output accuracy maintained for narrow or wide spans
  • Analog output resolution 0.0015% of span (16 bits), accuracy ±0.02% of span
  • Universal 85-264 Vac / 90-300 Vdc or 10-48 Vdc / 12-32 Vac power
  • DIN rail mount housing only 22.5 mm wide, detachable screw-clamp connectors

The Laureate process signal input transmitter and totalizer accepts 0-1 mA, 4-20 mA or 0-10V signals from flow meters and other transducers, such as watt meters, to track rate or totalized rate.

  • With a Standard Main Board, the transmitter output can track rate (such as gallons per minute or watts) or totalized rate (such as gallons or kilowatt hours) whether the transducer output is linear or requires square root extraction (differential pressure flow transducers).
  • With an Extended Main Board, the transmitter can also perform custom curve linearization (provided by a curvilinear spline fit with up to 180 data points), display 1/ rate (such as the time it takes a conveyor to pass through an oven), and perform batch control for repetitive fill operations. Such applications typically make use of optional dual solid state relays, which are available as options. External reset of totals is provided by a special connector.

A signal conditioner board converts the full-scale 0-1 mA, 4-20 mA or 0-10 V analog signal to a frequency of 10 kHz to 110 kHz. This frequency is determined by measuring period over a selected gate time (from 10 ms to 200 s) and taking the inverse of period. At the lowest frequency of 10 kHz and the minimum gate time of 10 ms, the transmitter is capable of 25 updates per second. Scaling is done mathematically. Totals are stored in nonvolatile memory in case of power loss.

Signal Conditioner Board for Laureate Analog Input Flow Rate Meter and Analog Flow Totalizer

Standard features of Laureate transmitters include:

  • 4-20 mA, 0-20 mA, 0-10V or -10V to +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 loops.
  • Serial communications output, 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.
  • Dual solid state relays, isolated, for alarm or control. Rated 120 mA at 140 Vac or 180 Vdc.
  • Transducer excitation output, isolated. User selectable 5V@100 mA, 10V@120 mA or 24V@50 mA.
  • Universal 85-264 Vac power. Low-voltage 10-48 Vdc or 12-32 Vac power is optional.

Easy Transmitter programming is via Laurel's Instrument Setup Software, which runs on a PC under MS Windows. This software can be downloaded from this website at no charge. The required transmitter-to-PC interface cable is available from Laurel (P/N CBL04).

Specifications Back to top

Laureate 4-20 mA & RS232/RS485 Transmitter & Totalizer for 0-1 mA, 4-20 mA or 0-10V Process Signals

Analog Input 0-1 mA 4-20 mA 0-10 V
Input resistance
Max current or voltage
1.00 kΩ
35 mA
50 Ω
70 mA
1.01 MΩ
600 V
Input Resolution
Span Tempco
Zero Tempco
Accuracy at 25¿½°C
Read Rate
6 digits
±0.0025% R/°C
±0.0005 FS/°C
±0.005% FS ± 1 count
25/sec (typical)


Analog Output (standard)
Output Levels
Compliance at 20 mA
Compliance at 10V
Output Resolution
Output Accuracy
Output Update Rate
Output Isolation
4-20 mA, 0-20 mA, 0-10 Vdc, -10 to +10Vdc (user selectable)
10V (0-500Ω load)
2 mA (5 kΩ or higher load)
16 bits (65,536 steps)
0.02% of output span
250V rms working, 2.3 kV rms per 1 minute test
Serial Data Output (standard)
Signal Types
Data Rates
Output Isolation
Serial Protocols
Modbus Compliance
Ethernet Connector
RS232/485 Connector
Digital Addresses
RS232 or RS485 (half or full duplex), jumper selectable
300, 600, 1200, 2400, 4800, 9600, 19200 baud
250V rms working, 2.3 kV rms per 1 min test
Modbus RTU, Modbus ASCII, Laurel ASCII
Modbus over Serial Line Specification V1.0 (2002)
RJ45 jack for 10/100Base-T Ethernet cable
Screw terminals for easy daisy chaining
247 for Modbus, 31 for Laurel ASCII
Transducer Excitation Output (standard)
Jumper Selection 1
Jumper Selection 2
Jumper Selection 3
10V @ 60 mA, isolated to 50V from signal ground
5V @ 50 mA, isolated to 50V from signal ground
15V @ 60 mA, non-isolated
Dual Relay Output (standard)
Relay Type
Load Rating
Two solid state relays, SPST, normally open, Form A
120 mA at 140 Vac or 180 Vdc
Power Input
Standard Power
Low Power Option
Power Frequency
Power Isolation
Power Consumption
85-264 Vac or 90-300 Vdc (DC operation not ETL certified)
10-48 Vdc or 12-32 Vac
DC or 47-63 Hz
250V rms working, 2.3 kV rms per 1 min test
2W typical, 3W with max excitation output
Electrical Connections
129 x 104 x 22.5 mm case
35 mm rail per DIN EN 50022
Plug-in screw-clamp connectors
Operating Temperature
Storage Temperature
Relative Humidity
Cooling Required
0°C to 55°C
-40°C to 85°C
95% at 40°C, non-condensing
Mount transmitters with ventilation holes at top and bottom.
Leave 6 mm (1/4") between transmitters, or force air with a fan.
Laureate LT transmitter pinout
Ordering Guide Back to top
Laureate 4-20 mA & RS232/RS485 Transmitter & Totalizer for 0-1 mA, 4-20 mA or 0-10V Process Signals
Click on the radio buttons to build a model number with pricing as shown below. Prices are in US dollars and do not include shipping or duty charges (export sales).
Please see our explanations and limitations applicable to pricing and online orders Prices shown are in US Dollars and are Laurel's manufacturer's suggested retail price (MSRP) in the USA. Orders are processed manually, not directly by our shopping cart system. You don't have to supply credit card information when placing an online order.

North American Orders. Laurel does not sell factory-direct in the USA or Canada. Online sales orders are filled through distribution. During the ordering process, you will have the chance to select an authorized Laurel distributor, or you can ask Laurel to refer you to a distributor. The distributor will then contact you to quote shipping, tax and duty (where applicable), and arrange for payment.

International Orders. If your ship-to address indicates that you are outside of the USA or Canada and Laurel has a distributor in your country, we will forward your order to that distributor for follow-up. If Laurel does not have a distributor in your country, we will email you an order acknowledgment and a pro forma invoice which states the product price, shipping charges, and wire transfer information, which includes a $25 bank wire transfer fee.

Questions about your order? Please email your distributor or sales@laurels.com
Configured model number LT60VF1
Configured price per model $235
Quantity 1
Extended price $235
LT  4-20 mA & RS232/RS485 output transmitter
LTE  4-20 mA & Ethernet output transmitter
Main Board
6  Standard Main Board
8  Extended Main Board
With Standard Main Board: Rate, square root of rate, or totalized rate from differential pressure flow transducers with a DC output.
With Extended Main Board:
Above plus linearization of nonlinear inputs, batch operation, 1/rate (time).
0  Isolated 85-264 Vac or 90-300 Vdc
1  Isolated 12-32 Vac or 10-48 Vdc
2  Power over Ethernet (for LTE only)
Input Type
Voltage-to-Frequency Converter
VF1  V-to-F Converter, 4-20 mA
VF2   V-to-F Converter, 0-1 mA
VF3  V-to-F Converter, 0-10V
Specify min input, min reading; max input, max reading.
CBL04  RS232 cable, 7ft. Connects RS232 screw terminals of LT
transmitter to DB9 port of PC.
CBL02  USB to RS232 adapter cable. Combination of CBL02 and CBL04
connects transmitter RS232 terminals to PC USB port.

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